Gravimetric Feeder

DOCUMENT COVER SHEET

PROJECT NAME : SIPAT SUPER THERMAL POWER PROJECT STAGE-I (3 x 660MW)

CONTRACT NO. : CS-9518-108-2(PART-A)-FC-COA-4313

I T E M : COAL FEEDER

DOCUMENT TITLE : GRAVIMETRIC FEEDER CONTROLS WRITE UP

C 12/8/05 Revised per M.O.M. of Nov. 22, 2005 RJN ------- BSP RJN

B 09/14/05 Revised per Owners Comments RJN --------- BSP MJP

A 04/22/05 First issue for approval RJN --------- BSP MJP

REV. DATE DESCRIPTION DGN CHK REVIEW APPR

National Thermal Power Corporation Ltd. (A GOVERNMENT OF INDIA ENTERPRISE)

DOOSAN HEAVY INDUSTRIES & CONSTRUCTION CO., LTD.

DOOSAN DOCUMENT NO. T04019-IC-V1220

NTPC DOCUMENT NO. 9518-108-11-K0-PVI-W-026 SHEET REV.

CATEGORY Information 1 C

NTPCDummyComment

Stock Equipment Company ATPD32400-140 OPERATION

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SYSTEM COMPONENT DESCRIPTION

Feeder Microprocessor Controls

The microprocessor feeder electronics control system is designed to operate in industrial and power plant environments where harsh conditions and frequent power disturbances exist. It uses special circuits, software subroutines, and nonvolatile memories to store data, programming and operating parameters. This allows the system to recover and keep the feeder running under control after a momentary power loss. The microprocessor electronics are contained in a NEMA rated electrical control cabinet with a glass door for keyboard access. The keyboard/display assembly is part of an environmentally sealed panel that is gasketed against the enclosure door. The feeder control consists of four hardware packages: a power supply, a CPU board, a keyboard/display assembly and a motor speed control. Additional input and output devices are available and can be formatted to a variety of requirements, both digital and analog.

The program chip used in the electronic system is part number D32400-140. (The last digit is the least significant digit of the program chip part numbers, and is variable and reserved for manufacturing use. It does not denote a change in programming or in equipment operation.)

Power Supply

The power supply board converts the customer's ac power into the regulated low voltages required to operate the control electronics. Input to the power supply is 117 V ac @ 50-60 hertz. This is converted by transformers into a series of low voltages which are rectified, filtered, and regulated. The voltages and the electronics they supply are listed below (refer also to Figure 1).

Voltage Device

+ 5 V dc Microprocessor, CMOS Display and Converter Cards

+ 10 V dc Load Cells and Amplifiers - 10 V dc Amplifiers + 15 V dc Calibration Probes - 15 V dc Opto-coupled Inputs and Calibration Probes

The 15 volt supplies are isolated from the logic and amplifier supplies. In addition, there is an unregulated voltage which is used to energize relay coils, provided from the filter side of the +15 volt supply. There are also two 20 V ac supplies for the isolated feed rate converter cards (A2) and/or (A3). Each converter card has on-board filters and regulators. The applied voltage from the power supply to the controller board is provided through a six-conductor cable.


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Input/Output Circuit Description

Located on the power supply board, the input/output circuits isolate the microprocessor and its associated circuitry from the electrical and control systems of the plant to eliminate malfunction from transients or noise.

All inputs to the CPU board are optically isolated at the power supply board. The system is designed to accept a maximum of twelve digital inputs or contact closures, a belt speed signal, an analog demand signal and a 20 mA serial communication input. All output signals are similarly isolated and include: seven power relays (each with two Form C contacts), one reed relay with two Form A contacts, two analog signals (one for the customer and one to operate the speed control), one 20 mA serial communication output, and two spare outputs that can be formatted to meet special requirements of the control system. Logic signals are transmitted to and from the power supply board to the microprocessor through a 50-pin ribbon cable.

A typical isolated input operates as follows. Incoming signals are used to bias a light emitting diode whose light output is directly proportional to


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input current. The light output of the diode is optically coupled to the base of a phototransistor. The collector lead of the transistor sinks current from the microprocessor to ground. Thus, inputs and outputs are electrically isolated.

A typical isolated output operates as follows. CPU signals are used to bias a light emitting diode and an optically coupled transistor, as with inputs. However, the transistor emitter sinks current to energize a relay coil and the relay contacts provide the output signal.

Input Signal Converter Card (A1)

The function of the input signal converter card is to convert the customer fuel demand signal to a normalized 0 to 10 kHz signal for interfacing with the microprocessor system. The fuel demand signal can be any standard control signal: current, voltage or potentiometer. The voltage and current mode cards are essentially the same except for a terminating resistor on the current mode card. The potentiometer input card supplies 5 volts across the customer's potentiometer and the proportionate signal is generated at the slider.

Frequency to Current Converter Card (A3)

The frequency to current converter card is used as a feedback module for customers who require an analog feedback. The output signal is unipolar and within a range of 20 mA. This circuit allows the digital electronics of the microprocessor to output a digital signal, while the customer receives a current feedback signal. In special applications, this circuit may be used to convert a digital motor speed demand signal into an analog demand signal.

Frequency to Voltage Converter Card (A2)

The frequency to voltage converter card is used as a feedback module for customers who require an analog feedback signal of -10 to +10 volts. This circuit allows the digital electronics of the microprocessor to output a digital signal, while the customer receives a voltage feedback signal. In special applications, this circuit may be used to convert a digital motor speed demand signal into an analog demand signal.

196NT CPU Board

The 196NT CPU board assembly is mounted on the hinged panel between the panel and the interior of the door to the microprocessor control cabinet, and is electromagnetically shielded from the rest of the feeder electrical controls. It contains a 16 MHz, 16 bit embedded controller, memories, and digital interface circuits. The analog circuits used to amplify and convert the load cell signals to a


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digital form are located on this board. The keyboard assembly with vacuum fluorescent (VF) display is directly cabled to the CPU board assembly.

The CPU board is the principal mechanism through which control of the system is achieved. Digital inputs and keyboard commands are processed by software algorithms which then route signals either to digital outputs or to the display as required. All digital I/O interfaces are isolated by circuits on the power supply board which prevent damage due to transients and prevent operational malfunction due to noise.

Interfacing between the microprocessor and the analog parts of the system is accomplished by conversion circuits. Signals which pass from an external analog device to the microprocessor first must pass through an analog to digital converter (voltage to binary number). When the microprocessor must operate an external analog device, its output is sent in the form of a frequency to a frequency to voltage or current converter card. This device is a digital to analog converter since its converts a binary number to either a voltage or a current. The A/D conversions for the load cell signals are made with a resolution of one part in 65,000 or 0.00153 percent. Other A/D conversions are made with a resolution of better than one part in 3200 or 0.03 percent.


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The microprocessor control configuration is shown in Figure 2. A transparent portion of the configuration is the software contained in a permanent memory. The software is written so that the most important system activities (such as the motor speed loop and demand signal input) are processed fast enough to allow good control to be achieved, while less important signals (such as relay outputs) are processed at a slower speed. This time multiplexing concept in the software program allows for better control of the process when a great number of tasks must be performed. As can be seen from the illustration, the only inputs directly accessing the CPU board are the keyboard and the load cells. All other I/O signals pass through optical isolation circuits located on the power supply which gives the system excellent noise immunity.

Microprocessor Memory

Programming of the microprocessor is done in the C programming language, which fully utilizes the 16 MHz operating speed of the microprocessor and expands the program memory space required to store the operating program. The system utilizes 128K bytes of available memory for program storage. There are also 32K bytes of random-access memory (RAM) for temporary storage of data during operation, and two nonvolatile memories for permanent and noise-immune storage of operating parameters and system totalizers.

The microprocessor accesses a type of permanent read-only memory (ROM) called a UV erasable EPROM for all operating instructions which form the system software program. This ensures that the control program instructions are not lost during a power interruption.

All operations involving the microprocessor utilize the transfer of information to and from memory. As the CPU executes its program by reading instructions from EPROM, data may be needed from one of the I/O interface chips, EEPROM or Bat-RAM (battery backed up RAM). This data may be stored in RAM for later processing or stored directly in the CPU in a storage location called a register. After the data is acted upon by the CPU, it may be stored in either its original memory location or in another. In all cases, the use of memory for storage of programs, data, and even memory addresses is an essential part of the microprocessor system.

Power Interrupt Protection Circuit

During operation, a temporary power interrupt may occur. This type of power failure may be frequent, and if the feeder memory data is erased during the interrupt, can shut down feeder operations even after power has been restored. To prevent this, a power interrupt protection circuit has been designed into the microprocessor controls which stores all incoming and outgoing data, and all operating parameters, as soon as the start of a


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power failure is detected. This allows the feeder to recover and keeps the system operating in an orderly manner when power is restored after a failure.

Alphanumeric Display/Keyboard

Commands are entered to the controls via the keyboard on the front panel of the microprocessor cabinet as shown in Figure 3. To operate the keyboard, it is necessary to open the small outer door by loosening its two thumbscrews. This door must remain tightly closed when the keyboard is not being used to maintain the NEMA rating of the control enclosure. The clear window allows the operation of the feeder to be checked without opening the door.

The keyboard consists of small switches which input data digitally by creating a low signal level (GND or binary number 0) when they are pressed. This signal is first stored in a specific memory location which is different for each key of the keyboard. The signal is then de-bounced to eliminate false signals. A true key press is then decoded into data which determines the function which is to be implemented and then the decoded data is placed in a queue for processing.

When the microprocessor is checking to see if the keyboard has been operated, it reads through the queue and implements any function allowed in the keyboard


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function table. That function may require further data (numbers) which are also read from the queue.

At the same time that pressed key signals are being stored in a decoded form in the queue, a de-multiplexer (decoder) reads the queue for any data which is numerical and drives the keyboard display with alphanumeric data. Thus, as numbers and function keys are entered, they are displayed.

The keyboard contains keys of two colors: white and blue. The white keys are the standard REMOTE/OFF/LOCAL selection of feeder operating mode and will be the keys most frequently used. To activate a mode selection, press the bottom center of the key below the LED light. The blue keys are functions and numbers that are activated by pressing the key in the exact center in the proper order.

When a key is pressed, the VF display will change to acknowledge that the membrane switch beneath the key has been activated successfully.


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Keyboard Commands

The three white keys with LED indicators at the upper center of the keyboard select the feeder operating mode, REMOTE, OFF or LOCAL. REMOTE allows the feeder to be controlled from the customer run permissive contacts and demand signal. OFF deactivates the feeder. LOCAL operates the feeder at a selectable speed. If there is material on the belt during LOCAL operation, the feeder will trip after a two-second delay.

NOTE

Pressing any of the white keys allows the feeder to operate in the selected mode. It also resets any alarm or trip indication, turning off the red panel indicators and opening the appropriate relay contacts.

The JOG key may be pressed and held to operate the belt drive motor for as long as the key is maintained. This command is used to check motor operation or to slowly move the belt for service. The feeder must be in the OFF mode to jog the belt.

Display Selection Keys

There are three totalized weight display selections: gravimetric total, volumetric total, and material total (combined totals of gravimetric and volumetric). The upper forty-character line of the VF display shows the totalized weight of material delivered. It may also be used to display function keys, number entry values and special functions. Whenever the display is not otherwise in use, it will show the totalized weight of material delivered.

Gravimetric is defined as material delivered with a functioning weighing system.

Volumetric is defined as material delivered when the weigh system is at fault and the amount of material is delivered using an assumed weight on the weigh span. The assumed weight is an average of what the material was known to weigh before the weighing system faulted. This weight is used to determine a nominal material density. Volumetric totalization has no guarantee of accuracy and may be at considerable error if material density is not uniform. Therefore, a separate total is kept.

Pressing TOTAL SELECT key selects the totalizer mode on the display. Repeated pressing of the TOTAL SELECT key will cycle through each of the three totalizer modes (Gravimetric Total, Volumetric Total or Material Total). The upper line of the display will show which mode is active. All totalizers are continually updated regardless of mode displayed. Whenever one of the totalizers reaches full capacity, it will roll over and begin again at zero.


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From time to time it may be desirable to reset the three totalizers back to zero. To do this, press and maintain: TOTAL RESET

IMPORTANT

There is no way to recall totalizer amounts once they have been reset.

The lower forty-character line of the VF display shows RATE, DENSITY or SPEED by pressing the INFO SELECT key. The display will cycle and can be stopped by releasing the key on the selected mode which appears at the left of the display.

RATE shows the operating feed rate of the feeder when in the gravimetric mode, or the equivalent feed rate using the average density of the material when in the volumetric mode.

DENSITY shows the density of material on the belt in the gravimetric mode in pounds per cubic foot or kilograms per cubic meter. In the volumetric mode, the density shown is based on an average density determined before the weight system faulted.

SPEED shows the feeder belt drive motor rpm.

Keyboard Disable Feature

The feeder programming includes a feature which will disable selected keys on the keyboard and thereby prevent accidental or unauthorized alterations to the operating parameters. To activate this feature, the customer may either install a jumper or close a key-operated selector switch between wires 107 and 117 in the control cabinet. The lower display line will indicate KEYS LOCKED on the right and all data entry is locked out. This closure disables the CAL 1, CAL 2 and TOTAL RESET keys, and only allows data verification in the TRIM and SETUP modes. To alter the feeder operating parameters, reset the totalizers, or calibrate the feeder, the jumper must first be removed or the key switch must be opened.

Status LEDs

The five LEDs on the keyboard panel indicate current operational status of the feeder.

a. RUNNING (green) is illuminated whenever the belt drive motor is energized.

b. FEEDING (green) is illuminated when the motor is energized and material on

the belt is sensed by paddle switch (LSFB).


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< SETUP > Enter Parameter 00-36

c. ALARM (red) indicates that a problem exists which requires attention, but is

not serious enough to immediately stop feeder operation.

d. TRIP (red) indicates that a serious problem exists and feeder operation has been stopped.

e. VOLUMETRIC (red) indicates that a fault exists in the weighing system or

its electronics which prevents the feeder from operating the gravimetric mode.

Diagnostic Error Codes

Whenever an ALARM or TRIP condition occurs, an error code number is stored internally to identify the source of the problem. To access the error code, press: ERROR RECALL.

A diagnostic message will appear in the display. For a description of the error code, refer to the section titled ERROR CODE.

NOTE

The CPU board is shipped from the factory with the real time clock disabled. To set the real time clock to the time and date, refer to the section titled SELF TEST.

Microprocessor Controls Set-Up

The microprocessor controller is tailored to specific feeders and customer needs by approximately 36 setup variables. Feeder-specific physical dimensions must be entered into the microprocessor controller in addition to user-selectable display modes and set points. These values are stored in permanent memory and only have to be entered once.

The setup procedure for changing these parameters consist of referencing a specific parameter by a two-digit address and associating either a value or an instruction with this address. An instruction is usually a single-digit number which sets the controls or display to operate in a predetermined way. A value is a feeder set point or dimension which is used by the microprocessor in its control sequence.

To access the parameter changing mode, the SETUP key is pressed. The microprocessor display prompts the operator to enter the address (00-36) for the parameter that needs to be viewed or changed. The display reads:


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< SETUP 05 > 5.000 Tons/hr Maximum Feed Rate

The microprocessor will select a default address if one is not selected by the operator in 4 seconds. Other addresses can then be accessed by pressing the UP or DOWN arrow keys. For each address, the display shows the address number, the current parameter's value, units of measure, and a brief description. For example, the display may appear as follows for Address 05.

The microprocessor controls are capable of displaying units of weight in pounds, kilograms, U.S. tons, and metric tons. To choose alternate units for setup parameters that are values, press the SETUP key until the desired units are displayed. The microprocessor recalculates the displayed value to accommodate the new units. Each of the setup parameters that are values have independent units. Changing units for one parameter does not affect the other parameters.

To alter a parameter value, key in the new value on the numeric keyboard and press the ENTER key. As the new value is entered, it is displayed next to the old value. If a typographical error is made on entry, the CLEAR key blanks the current new entry without affecting the original value.

The value of any setup parameter can be viewed in any of the modes (REMOTE, OFF, LOCAL). Any of the setup parameters can be altered in the OFF mode. Motion-dependent setup parameters cannot be changed when the feeder is running (REMOTE or LOCAL). The display will then warn the operator with the message: "Feeder must be OFF to change."

NOTE

Pressing the OFF key de-energizes the feeder motor.

Pressing the EXIT key or OFF key immediately ends the setup operation. The setup operation will also end after 5 minutes of keyboard inactivity.

Use the following general instructions when entering setup values:

1. Select the units of measure (pounds, kilograms, etc.) by pressing the SETUP key

until the desired units are displayed.

2. Enter numbers as if using a pocket calculator.

3. When entering a decimal value which is less than 1.0, a zero must be entered before the decimal point, as in 0.15.


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4. The microprocessor displays three decimal places for most values, but internally keeps six digits of accuracy (ANSI/IEEE single precision). If more than six digits are entered at the keyboard, the microprocessor round or truncate the value entered.

5. If a decimal point is used at a setup address which requires a coded entry, the

microprocessor will ignore the decimal point.

6. If a mistake is made, press CLEAR to erase the entry and start again.

7. Press ENTER to store the value in memory.

8. If a value for a setup parameter is entered which exceeds the usable range of the specific setup parameter, the microprocessor displays the message OUT OF RANGE, and the original value for that specific setup parameter is used. Changing the units (e.g., pounds to kilograms) automatically changes the usable range.

9. The keyboard may have a lockout feature which prevents any change from being

made to the setup parameters. The lockout feature is either a switch or a jumper wire between terminals 107 and 117 in the microprocessor cabinet. To remove the lockout feature so that setup parameters may be entered, either open the switch or deenergize the controls and remove the jumper wire.

10. It is recommended that the setup parameters be reviewed for accuracy after all

initial entries have been made.

SETUP FUNCTIONS

Initiate the setup mode by pressing the OFF key on the microprocessor keyboard. Then press: < SETUP > 00.

NOTE

If a delay of five seconds or more occurs after SETUP is pressed, the MPC will default to the last setup address accessed. Use the UP or DOWN arrow to return to 00.

Feed Rate Set Point (Address 00)

This is the feed rate set point used when the feeder is operating in the REMOTE mode controlled by feed rate set point (see Address 03, option 2). The available units for this parameter are pounds/hour, tons/hour, kilograms/second, kilograms/hour, and metric tons/hour.


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Example: If the feeder will operate in the REMOTE mode controlled by the feed rate set point, press: 18.25 tons/hr ENTER

If the feeder will operate in the REMOTE mode controlled by the analog customer feed rate demand signal, this address is not recognized.

Speed Set Point RPM (Address 01)

This is the operating speed of the belt drive motor in the LOCAL and CALIBRATION modes, and also in the REMOTE mode when the feeder is controlled by speed set point (see Address 03, option 5). The value must be less than the value entered for the motor maximum speed (see Address 29) and greater than the value entered for the motor minimum speed (see Address 30).

Example: If the feeder is to operate at 1000 rpm, press:

until < SETUP 01 > appears, then 1000 ENTER

Initial Density Estimate (Address 02)

This is an initial density estimate of the material which will be fed and is used to initialize the average running density whenever a new value is entered. The average running density calculated by the microprocessor can be viewed in . Available units for the parameter are pounds/cubic foot or kilograms/cubic meter.

Example: If the feeder will be feeding material with an expected density of 50

pounds per cubic foot, press:

until < SETUP 02 > appears.

Then press SETUP until the units appear as lbs/cu ft

Press 50.0 ENTER

Run Mode (Address 03)

The feeder can be run in REMOTE operation in any of eight run modes, according to the following table:

Run Mode Operating Characteristics

0 Analog Customer Feed Rate Demand. The feeder will seek to

match a feed rate demand from the analog customer demand input. This demand may be 4-20 mA, 0-10 volts, etc. Note: It is necessary to align the input converter card according to the


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procedure in Section 3.3.1 before operating the feeder. The limits on the feed rate demand signal are set by the minimum (Address 06) and maximum (Address 05) feed rates of the feeder.

1 Raise/Lower Customer Feed Rate Demand. This mode increases or decreases an internal feed rate set point depending upon the raise or lower contact closures. The limits on the raise/lower control are set by the minimum (Address 06) and maximum (Address 05) feed rates of the feeder.

2 Feed Rate Set Point. The feeder will deliver material at the rate

contained in the feed rate set point (Address 00).

3 Analog Customer RPM Demand. The feeder will seek to match a speed demand from the analog customer demand input. The value entered in Address 29 determines the maximum speed that can be attained and the value in Address 30 determines the minimum speed. This mode permits net material weighing within a volumetric rate feed system. NOTE: It is necessary to align the input converter card according to the procedure in Section 3.3.1 before operating the feeder.

4 Raise/Lower Customer Speed Demand. This mode increases or decreases an internal motor speed set point depending upon the raise or lower contact closures. The value entered in Address 29 determines the maximum speed that can be attained and the value in Address 30 determines the minimum speed.

5 Speed Set Point. The feeder will operate at the constant speed

contained in the motor speed set point Address 01. This permits a constant volume per second delivery but with electronic weighing, like a belt scale.

6 Feed Rate Serial. The feeder will deliver material at a constant

feed rate. This is set by a command sent through the serial port.

7 RPM Serial. The feeder will deliver material at a constant motor speed. This is set by a command sent through the serial port.

Example: If the feeder will be controlled by the analog customer demand input,

press: until < SETUP 03 > appears, then 0 ENTER


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Display Select (Address 04)

This parameter specifies which units of measure the microprocessor will use to display feed rates, densities, belt travel and totals.

Units of Measure Selection Chart

Unit Options

Description

Units of Measure

0

Feed rate; Density; Belt travel; Totals

U.S. tons/hour; pounds/cubic foot; inches; U.S. tons

1


pounds/hour; pounds/cubic foot; inches; pounds

2


metric tons/hour; kilograms/cubic meter; meters; metric tons

3


kilograms/hour; kilograms/cubic meter; meters; kilograms

4


kilograms/second; kilograms/cubic meter; meters; kilograms

Example: If the desired feed rate unit of measure is U.S. tons per hour, density is pounds per cubic foot, belt travel is inches and totals is U.S. tons, press:


Maximum Feed Rate (Address 05)

This is the maximum feed rate that the feeder can achieve in the REMOTE mode following a demand signal or a RAISE command. The available units for this parameter are pounds/hour, tons/hour, kilograms/second, kilograms/hour and metric tons/hour.

Example: If the maximum permissible feed rate is 77 tons per hour, press:


Then press SETUP until the units appear as tons/hr

Press 77 ENTER

Minimum Feed Rate (Address 06)

This is the minimum feed rate that the feeder can achieve in the REMOTE mode following a demand signal or a LOWER command. The available units for this


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parameter are pounds/hour, tons/hour, kilograms/second, kilograms/hour and metric tons/hour.

Example: If the minimum permissible feed rate is 4.68 tons per hour, press:

until < SETUP 06 > appears, then 4.68 ENTER Remote Data Logging Totalizer Increment (Address 07)

This sets the amount of material registered on a remote totalizer for every pulse of the data logging output. A typical value is 100 units (pounds, U.S. tons, kilograms, or metric tons). Press:


Demand Mode (Address 08)

This is a switch denoting where the speed control demand signal and secondary feedback are present. There are two cases:

Demand Mode Secondary Feedback Source

0 The feeder has an eddy current clutch connected to lines 131

and 132, and a secondary feedback from output socket A2, or

The feeder has a dc or variable frequency drive motor speed control with a signal converter connected to lines 131 and 132.

1 The feeder has a dc or variable frequency motor speed

control with a drive card in slot A2, and secondary analog feedback available via lines 131 and 132 using an optional signal transmitter.

Example: If the feeder motor is equipped with an eddy current clutch, press:


Tachometer Type (Address 09)

This parameter specifies the type of tachometer used, according to the following table:

Value Tachometer

0 60-Tooth Gear


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1 40-Tooth Gear

2 Ac Tachometer - 18 cycles (36-pole)

3 Ac Tachometer - 12 cycles (24-pole)

Example: If a 24-pole ac tachometer is in use, press:


Weigh Span (Address 10)

The weigh span is the distance between the centers of the weigh span rollers expressed in one of the following units: inches, centimeters, millimeters or meters. Enter up to two decimal places if necessary.

Example: If the distance between weigh span rollers is 38.292 inches, press:


Then press SETUP until the units appear as "in".

Press 38.3 ENTER

Volume (Address 11)

This represents the volume of material on the weigh span. It is calculated from the following dimensions: leveling bar height, material stream width, corner cut-off dimensions, and weigh span length. Round the entry to three decimal places. The available units for this setup parameter are cubic inches, cubic feet, cubic centimeters, or cubic meters.

The following dimensions are required for this calculation:

Leveling bar height - 7" Material stream width - 24" Weigh span length - 38.3" Cut-off dimensions - 2-7/8" x 4-7/8"

(Note that the two cut-off corners together form a rectangle.)

Example using the sample dimensions listed:

1. Cross Sectional Area = Total Area - Cut Off Area

= (Bar Height x Mtl. Stream)-(Height x Width) = (7" x 24") - (2.875" x 4.875")


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= 153.99 sq. in.

2. Convert square inches to square feet.

144 sq. in. = 1 sq. ft.

3. Volume on weigh span = Cross sectional area x weigh span length = 1.07 sq. ft. x 3.191 ft. = 3.41 cu. ft.

To enter this sample value, press:


Then press SETUP until the units appear as "cu ft."

Press 3.41 ENTER

Calibration Probe Span (Address 12)

This is the linear length of belt being sensed by the calibration probes and is expressed in inches, centimeters, millimeters or meters.

Example: If the center distance between calibration probes is 38.700

inches, press:


Then press SETUP until the units appear as "in".

Press 38.7 ENTER

Calibration Weight (Address 13)

This value represents the total weight of the calibration weight(s). The value of each calibration weight is stamped on the end of the weight weldment. Possible units for this parameter are pounds or kilograms.

Example: A feeder has two 25-pound calibration weights. Enter the total,

rounded to three decimal places. Press:



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Then press SETUP until the units appear as "lbs".

Press 50 ENTER


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Motor Speed Control Servo Loop Gain (Address 14)

This parameter is predetermined for each particular motor/control combination and should not be altered without consulting Stock Equipment Company. Typical values are listed in the following table:

Value Motor/Control Combination

4800 Eddy Current Clutch Speed Control

2000 DC Motor Speed Control

4000 AC Variable Frequency Drive



NOTE

Incorrect values may cause wild instability in motor speed.

Motor Speed Control Servo Loop Rate Feedback Gain (Address 15)

This parameter, like the servo loop gain, is predetermined for each particular motor/control combination and also can cause uncontrolled motor behavior if improperly set. Its value is highly dependent upon the amount of acceleration/deceleration control used in the speed control. Typical values are listed in the following table:

Value Motor/Control Combination

14000 Eddy Current Clutch Speed Control

14000 DC Motor Speed Control

8000 AC Variable Frequency Drive




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Discharge Pluggage Delay (Address 16)

If the feeder is equipped with a discharge pluggage sensor, this parameter sets the delay after closure of the discharge pluggage switch contacts until the feeder is tripped. To disable this function if a discharge pluggage sensor is not provided, enter "0"; otherwise, the delay must be entered in seconds as:

1/2 second = 0.5 2 seconds = 2.0 5 seconds = 5.0 (this is the maximum allowable delay)

Example: If the feeder is to be stopped after a 2-second delay, press:

until < SETUP 16 > appears, then 2.0 ENTER

Belt Motion Monitor Delay Time (Address 17)

If the feeder is equipped with a belt motion monitor, this parameter specifies the maximum time interval, in seconds, between pulses received from the motion monitor magnetic pick-up before the belt can be identified as not moving. The interval is determined when the feeder is operating at its minimum design feed rate and is equal to the time necessary for the pulley or roller which inputs the sensor to make one complete revolution, divided by two, plus ten percent. Therefore, time intervals for motion monitors mounted to the tension roll or belt take-up pulley will be considerably longer than those for sensors mounted to the weigh span roller. To disable this function if a belt motion monitor is not provided, enter "0".

Example: If the motion monitor is mounted to the weigh span roller which

makes one revolution every 20 seconds at minimum feed rate, the time interval between pulses before the belt is certain not to be moving is: 20 2 = 10 + 10% = 11 seconds. Press:


Level/Temperature Sensor Trip Delay (Address 18)

If the bunker to pulverizer system includes a level monitor, this parameter specifies the delay after a material void is detected in the downspout before the feeder is tripped. The delay is expressed as the volume of material delivered from the downspout after the void is sensed. The available units for this setup parameter are cubic inches, cubic feet, cubic centimeters or cubic meters.

To disable this function, enter 0. Enter 0.1 for an immediate trip.


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As an example, the following data are required for this calculation: downspout radius, downspout height (from level monitor elevation to coupling) and maximum feeder operating pressure differential.

The following example uses units of feet:

Downspout radius: 1 ft. Downspout height: 12 ft. (from level monitor elevation to coupling) Max. feeder operating pressure differential: 25 inches of water

Example using the sample dimensions listed:

1. Volume in downspout = x radius of downspout squared x height

= 3.14 x (1)2 x 12 = 37.68 cu. ft.

2. The volume of material which must remain in the downspout to safely

maintain a head seal is based upon 2 inches of material per inch of feeder operating pressure differential.

25 in. H2O x 2 in. per inch H2O = 50 in. of material required

3. If the downspout height from level monitor elevation to the downspout

coupling at the feeder is 144 inches (12 ft), and if 50 inches of material must remain in the downspout to preserve the head seal, then the amount of material which may safely be fed before deactivation of the feeder is:

144 in. - 50 in. = 94 in.

4. To determine what volume of material may be fed, set up a proportion as

follows. Inches of material which may be fed is to total inches of downspout height as volume of material which may be fed is to total downspout volume.

X = 24.6 cu. ft.

To set up using these sample dimensions, press:


Then press SETUP until the units appear as "cu ft"

Press 24.6 ENTER


2-23

Weight Signal Filtering (Address 19)

This sets the amount of filtering between load cell measurement. It is used where there is considerable mechanical vibration at the feeder or when the belt has an inconsistent weight.

The recommended initial setting is 4. Increasing the value by one, doubles the degree of filtering; decreasing it by one, halves the degree of filtering. A value of zero provides no filtering, and 8 provides the maximum degree of filtering available.

Example: Using the recommended initial setting. Press:


Feedback Signal Filtering (Address 20)

This sets the amount of filtering directly on the feedback signal. More filtering smooths out the feedback signal but also makes it slower to respond. Less filtering increases the response but with more variation. This parameter should be adjusted according to individual plant requirements.

The recommended initial setting is 2 or 3. Increasing the value by one, doubles the degree of filtering; decreasing it by one, halves the degree of filtering. A value of 8 provides maximum filtering. For smooth response in noisy environments, enter 4 or 5. For fastest response (with greatest variation), enter 0 (this is suggested for PID control loops).

Example: Using the recommended initial setting. Press:


Feedback Filter Override Threshold (Address 21)

When the feedback is filtered and a large scale step change is made in demand, the filter on the feedback can be bypassed to allow quick reaction to this large change. This parameter specifies how large the change must be before the filter is overridden. The typical value is 15 percent (entered as "0.15"), so that if the feed rate demand changes more than 15 percent, the filter is bypassed. In general, a smaller percentage more accurately reproduces the output but may result in more feedback variation due to small, random changes in the weight of the belt.

Example: Using the typical value. Press:



2-24

Belt Travel Revolutions (Address 22)

This sets the total belt travel (in belt revolutions) used for simulated material tests (see Self Test 13). Best test results will be obtained if multiples of one complete belt revolution are entered, although partial belt revolutions will be accepted.

Example: To set the material test duration to five belt revolutions, press:


(Address 23)

This setup function address is not used in this application.

Paddle Feedback Permissive (Address 24)

This parameter specifies how the feeder's analog feedback signal reacts to the absence of the material on belt paddle as determined by the coal-on-belt limit switch input:

Value Feedback

0 The analog feedback signal is proportional to the RATE

regardless of the position of the material-on-belt paddle switch.

1 If the coal-on-belt paddle switch indicates an empty belt, the analog feedback shows zero output (i.e., 4 mA in a 4-20 mA configuration, 0 volts in a 0-10 volt configuration, etc.)

Example: "0" is the preferred value. Press:


Communications Unit Number (Address 25)

This number must be assigned to differentiate individual feeder units when a number of units are connected to a centralized computer control system for data logging purposes. Numbers 1 to 255 may be entered here as necessary. When a value of 0 is entered, serial communications are disabled.

Example: A particular feeder is to be designated No. 5. Press:



2-25

Mode Select Enable/Disable (Address 26)

This parameter specifies the source of control for the feeder REMOTE, OFF, or LOCAL operating modes according to the following table:

Value Mode Input(s) Enabled

0 Feeder operating mode can be established only by pressing one

of the three white keys on the microprocessor keyboard.

1 The operating mode and white keys on the microprocessor keyboard are governed by a remotely located mode selector switch when the microprocessor control cabinet is feeder mounted, or a feeder mounted mode selector switch when the microprocessor control cabinet is remotely installed. When the selector switch is placed in the REMOTE position, the feeder will go immediately into remote mode and respond to the feeder start permissive. When the selector switch is placed in the LOCAL position, the feeder will immediately begin to operate in the local mode. The feeder OFF key can always be used to deactivate the feeder regardless of the position of the selector switch.

To restart the feeder after the feeder OFF key is pressed, proceed as follows. For operation in the remote mode, simply press the REMOTE key; for operation in the local mode, the selector switch must be turned first to OFF, then turned to LOCAL. The feeder JOG key will respond only when the selector switch is in the OFF position.

2 Feeder operating mode can be established only by means of a

feeder-mounted mode selector switch when the microprocessor control cabinet is also feeder mounted, or when a remote feeder control cabinet has installed within it both a microprocessor and a feeder mode selector switch. The three white keys on the microprocessor keyboard are disabled.

Example: Feeder mode selection is through the microprocessor keyboard. Press:



2-26

FRI Output Frequency (Address 27)

This parameter specifies the frequency of the feed rate indicator output which corresponds to hertz per ton per hour, hertz per kilogram per second, hertz per metric ton per hour feedrate.

Example: Using the standard feed rate indicator with output of 10 hertz per ton

per hour. Press:


Then press SETUP until the units appear as "Hz/tph"

Press 10 ENTER

Raise/Lower Contact Input Response Time (Address 28)

When the feeder is operating in the REMOTE mode controlled by either RUN mode 1 or 4 (see Address 03, option 1 or 4), this parameter will allow you to vary the time to go from 0 percent to 100 percent feed rate. It has a range of 5-300 and a response time of 60 percent of the number entered based on a step input of 0 percent to 100 percent feed rate. A starting value of 100 is recommended to get a response time of 60 seconds.

Example: If 100 is the value required, press:


Maximum Motor Speed Clamp (Address 29)

This address determines the maximum rpm at which the motor will run. Address 01 (speed set point rpm) will be changed automatically to be with in this limit.

When the feeder is running in rpm demand mode (Address 03, option 3) or in the RAISE/LOWER rpm mode (Address 03, option 4), this maximum rpm value will correspond to the maximum demand signal.

Example: The motor is rated at XXXX rpm maximum, press:

until < SETUP 29 > appears, then XXXX ENTER

Minimum Motor Speed Clamp (Address 30)

This address determines the minimum rpm at which the motor will run. Address 01 (speed set point rpm) will be changed automatically to be within this limit.


2-27

When the feeder is running in rpm demand mode (Address 03, option 3) or the RAISE/LOWER rpm mode (Address 03, option 4), this minimum rpm value will correspond to the minimum demand signal.

Example: The minimum motor rpm is XXX rpm, press:

until < SETUP 30 > appears, then XXX ENTER

(Address 31)


(Address 32)


Weight Signal Gain Factor (Address 33)

This address specifies the gain set on the load cell A/D converter according to the following table:

Value Gain Factor

0 This is the normal setting. It should always be used when normal

Stock load cells (3mV/V) are connected directly to the 196NT controller.

1 This is a high gain setting used when low output (less then

3mV/V) load cells are connected directly to the 196NT controller. It should not be used with Stock load cells.

2 This is the normal setting when the load cells are connected

through a remote load cell amplifier.

3 This is the high gain setting when the load cells are connected through a remote load cell amplifier.

NOTE

The feeder must be recalibrated after setup Address 33 has been changed.

Example: To use the normal gain factor, press:



2-28

(Address 34)


Remote Totalizer Pulse Width (Address 35)

This address specifies the duration of the remote totalizer (K8 relay) output pulse. This value is rounded to the nearest 50 ms by the microprocessor. It has a range of 0.005 to 2.0 seconds.

The relay OFF TIME must be at least as long as the ON TIME. If this register is set up incorrectly, the remote TOTALIZER INDICATOR (TCI) will not display the actual totalized amount. The value of this register multiplied by the value of address 07, specifies the MAXIMUM feed rate that the feeder can deliver.

Example: Maximum Feed Rate = 200000 Lbs. per hour.

Address 07 = 100 Lbs.

This is equal to 1.8 seconds per pulse. Address 35 must be programmed to 0.9 or lower. Press:


Test Chain Weight (Address 36)

The value entered into this register represents the total weight of the optional test chains in units of weight per unit length and is used at the end of SELF TEST 13 to calculate the feeder weighing error. When test weights are not used (a zero load


2-29

test), this address should be set to a value of zero. Units available for this parameter are: pounds/inch, kilograms/meter, kilograms/centimeter, kilograms/millimeter. The weight of each test chain is stamped on the end of the chain assembly.

Example: A set of six test chains has the following weights marked in Lbs./in:

0.7212, 0.7214, 0.7213, 0.7215, 0.7214, 0.7212. Enter the TOTAL SUM of each chain rounded to four decimal places.

until appears, then Press:

SETUP until the units appear as Lbs./in.

Then Press: 4.3280 ENTER

Feeder Operation Specifications (Refer to the original manual OPERATION Section)

The data that follows is copied from OPERATION section of the original manual and it is used to determine the feeder operating parameters:

1. Gear Reduction 2. Leveling Bar Height

3. Weigh Span Length 4. Calibration Probe Span Length 5. Area Of Cross Section Under Leveling Bar 6. Specified Density of Material Handled 7. Maximum Capacity Feed Rate 8. Minimum Capacity Feed Rate 9. Maximum Capacity Motor Speed (Based on XX lbs./cu. ft. density) 10. Tachometer Type 11. Input Signal 12. Feedback Signal

Feeder Parameter Table


2-30

The following table summarizes all the operating parameters of the microprocessor control system. The values entered in the preliminary value column are to be copied from the existing microprocessor control and are used for guidance during equipment start-up. They should be checked and changed as required in accordance with actual job site conditions and, when verified, recorded in the final value column for permanent reference.

Address

Function

Preliminary

Value

Final Value

00

Feed Rate

01

Speed Set Point (rpm)

02

Initial Density Estimate (pounds per cubic foot)

03

Run Mode Select

04

Display Select

05

Maximum Feed Rate (tons per hour)

06

Minimum Feed Rate (tons per hour)

07

Totalizer Increment (pounds per pulse)

08

Demand Mode

09

Tachometer Type

10

Weigh Span Length (inches)

11

Volume (cubic feet)

12

Calibration Probe Span (inches)

13

Calibration Weight (pounds)

14

MSC Servo Loop Gain

15

MSC Servo Loop Rate Feedback

16

Discharge Pluggage Delay

17

Belt Motion Monitor Delay (seconds)

18

Level/Temperature Sensor Trip Delay

19

Weight Signal Filtering

20

Feedback Signal Filtering

21

Feedback Filter Override Threshold

22

Belt Travel Revolutions

23

(Not used in this application)

24

Paddle Feedback Permissive

25

Communications Unit Number

26

Mode Select Enable/Disable

27

Remote FRI Frequency @ 1 tph

28

Raise/Lower Response Time

29

Maximum Allowable Motor Rpm


2-31

Address

Function

Preliminary

Value

Final Value

30

Minimum Allowable Motor Rpm

31


32


33

Weight Signal Gain Factor

34


35

Remote Totalizer Pulse Width

36

Test Chain Weight

Acoustic Flow Monitor The Acoustic Flow sensor is designed specifically for early detection of material flow stoppage in the valve preceding the feeder. The basic principal used in the system is that of detecting the absence of sound of material motion when a stoppage exists. As material flows through the valve and downspout, sonic waves are generated at the friction interface between the material and valve wall, material and sensor probe, and material particles moving against one another. This sound vibration is transmitted as a physical motion through the tip of the sensor probe. This motion is proportionally converted by a piezoelectric element to an electrical signal which is transmitted to the control unit. Within the control unit the signal is amplified and filtered to eliminate non-flow related interference. The incoming signal activates and maintains a material motion status. In the event of a stoppage in the valve or downspout, or when a valve or downspout is full or is partially full of non-moving material, the material motion signal drops below a set point, providing a contact closure which indicates that material flow stoppage has occurred. An adjustable 1 second to 15 second time delay on this relay contact is included to prevent nuisance alarms. Additionally, the overall system gain and the trip threshold set point are adjustable. Since the pulverizer usually operates at a pressure different than that of atmospheric pressure, the feeder supplying it becomes pressurized/depressurized accordingly. Moreover, because the bunker outlet is essentially at atmospheric pressure, a head seal is necessary to facilitate material flow into the feeder. The head seal is the actual column of material in the valve/downspout which, over its height, evenly dissipates the pressure in the feeder to atmospheric at the bunker outlet. It must be of sufficient height to prevent fluidization of the material caused by an excessive pressure drop over too small a portion of the column. When a stoppage occurs above the feeder, a void forms beneath it as the feeder continues to feed, jeopardizing the head seal. When a stoppage is detected in the valve/downspout by the Acoustic Flow monitor unit, a signal is transmitted from the Acoustic Flow control unit to the microprocessor.

B


2-32

The microprocessor then begins to measure the volume of material passing over the weigh span by using the material density it has internally calculated to derive the volume of material from its weight. When the volume that has been programmed into the set-up parameter at Address 18 in the microprocessor has been fed, the microprocessor examines the input to see if material flow has been re-established or if the stoppage still exists. If material flow has resumed, feeding continues normally; if it has not, the feeder is tripped immediately and an error code (Code 13) giving the reason for the trip is displayed.

1

For: Doosan Heavy Industries American Corp. Project: SIPAT Units #1, #2 & #3 India Purchase Order No.: 110104180/N003-05KX Stock Equipment Company Sales Order: S.O. 10102-0000, 10103-0000, 10104-0000 File: SIPAT_Logic_rev_0.doc Date: 12-12-2005

Stock Equipment Company 196NT Controller Logic

(Reference Logic Diagram, Stock 196NT Microprocessor Dwg. No. A1-001517)

Microprocessor Memory The microprocessor utilizes 128K bytes of available memory for program storage. There are also 32K bytes of random-access memory (RAM) for temporary storage of data during operation, and two nonvolatile memories for permanent and noise-immune storage of operating parameters and system totalizers. A type of permanent read-only memory (ROM) called a UV erasable EPROM for all operating instructions, which form the system software program. This ensures that the control program instructions are not lost during a power interruption. All operations involving the microprocessor utilize the transfer of information to and from memory. As the CPU executes its program by reading instructions from EPROM, data may be needed from one of the I/O interface chips, EEPROM or BatRAM (battery backed up RAM). This data may be stored in RAM for later processing or stored directly in the CPU in a storage location called a register. After the data is acted upon by the CPU, it may be stored in either its original memory location or in another. In all cases, the use of memory for storage of programs, data, and even memory addresses is an essential part of the microprocessor system. Input and Output Signals Input Signals Input signals to the CPU consist of analog signals (such as feed rate demand or feeder belt drive motor tachometer), keyboard inputs for operation and/or parameter entry, and contact inputs from sensors on the feeder to enable the CPU to monitor the operating status of the feeder or a customer start/stop command for feeder operation.

2

Output Signals Output signals to the CPU consist of analog signals (such as feeder feed rate feedback, or speed control signal to the motor speed control), or feeder status contact outputs (such as ALARM, TRIP, FEEDER IN REMOTE) provided for customer use. Feeder Modes The feeder is capable of being operated in three modes: OFF, REMOTE, or LOCAL/CALIBRATE. OFF deactivates the feeder. REMOTE allows the feeder to be controlled from the customer run permissive contacts and demand signal. LOCAL operates the feeder at a selectable speed or puts it in the CALIBRATE mode when used in conjunction with the CAL 1 and CAL 2 keys. FEEDER OUTPUTS Trip Relay K1 Energized under any of the following conditions:

1. The belt drive motor or motor speed control is producing a serious motor speed deviation from the desired speed, and the motor tachometer speed is greater than +/- 1,000 RPM for 10,000 RPM seconds. ERROR CODE 12 RPM deviation is displayed on the vacuum fluorescent display.

2. Motor speed is zero after a 3 second delay and the feeder is in LOCAL or CALIBRATE mode. ERROR CODE 03 tach feedback is displayed on the vacuum fluorescent display.

3. There is no belt motion detected and MPC Address 17 is set to 1 to indicate that the feeder is equipped with a belt motion monitor, the feeder is in REMOTE, a customer START contact has been energized, and motor speed demand is greater than 50 RPM. ERROR CODE 04 motion monitor is displayed on the vacuum fluorescent display.

4. After a 4 second delay in either LOCAL or CALIBRATE and after a two second delay with material on the belt. ERROR CODE 08 Material in LOCAL is displayed on the vacuum fluorescent display.

5. The feeder discharge is plugged for a time longer than the delay programmed into MPC Address 16. ERROR CODE 07 discharge plugged is displayed on the vacuum fluorescent display.

6. The volume of material specified in MPC Address 18 has been delivered and the Acoustic Flow Monitor continues to indicate that a void remains in the valve/downspout, or an over-temperature condition has been sensed inside the feeder if a temperature switch has been provided. ERROR CODE 13 Level or temp sensor is displayed on the vacuum fluorescent display.

3

7. After a two second delay the motor speed control has been determined to not be running and the feeder is in the RUN mode. ERROR CODE 11 Motor starter is displayed on the vacuum fluorescent display.

Tachometer Select Relay K2 Energized under the following conditions:

1. With the feeder running in either REMOTE, LOCAL, or CALIBRATE mode, a signal has not been received by the microprocessor from the primary tachometer for 3 seconds. ERROR CODE 21 Primary Tachometer Failure is displayed on the vacuum fluorescent display.

Remote Relay K3 Energized under the following conditions:

1. The REMOTE key has been pressed and the feeder is not in the REVERSE mode.

Volumetric Relay K4 Volumetric is defined as material delivered when the weigh system is at fault and the amount of material is delivered using an assumed weight on the weigh span. The assumed weight is an average of what the material was known to weigh before the weighing system faulted. This weight is used to determine a nominal material density. Volumetric totalization has no guarantee of accuracy and may be at considerable error if material density is not uniform. Therefore, a separate total is kept. Energized under any of the following conditions:

1. The two load cell signals disagree by more than 12.5% after two seconds. 2. The Analog to Digital converter is defective. Either a) the CPU detected a not

READY signal from the A/D converter (pin 22 is a logic high signal). ALARM relay K7 is also energized. This alarm will automatically reset when the CPU can read the A/D converter again; or b) there is a possible loss of the +10 VDC supply. ERROR CODE 02 A/D read is displayed on the vacuum fluorescent display.

3. There is an A/D converter over range. Possibly caused by: a defective load cell and/or load cell cable; excessive weight on the weigh span; incorrect load cell sense line voltages to pins 14 and 15 of the A/D converter. ALARM relay K7 is also energized. This alarm automatically resets when the over range condition is cleared; defective A/D converter (analog front end components). ERROR CODE 01 A/D over range is displayed on the vacuum fluorescent display.

4. There is an A/D calibration error. Possibly caused by inconsistent results during automatic electronic self-calibration of the A/D converter; defective A/D converter; the reference voltage on pins 14 and 15 of the A/D converter is

4

unstable; possible loss of the +10 VDC supply. ALARM relay K7 is also energized. This alarm resets when the electronic calibration results are consistent.

Running Speed, Totalizer, and Feed Rate Feedback signals are all Volumetric when VOLUMETRIC relay K4 is energized. Feeding Material Relay K5 Energized under the following conditions: There is material on the belt and the feeder motor is running Feeder Run Relay K6 Energized under the following conditions:

1. When the feeder is in the REMOTE mode and the customer START contact has been energized.

2. When the feeder is in the LOCAL mode and there is no material on the belt.

Alarm Relay K7 Energized under any of the following conditions:

1. The two load cell signals disagree by more than 12.5% after two seconds. The Analog to Digital converter is defective. Either a) the CPU detected a not READY signal from the A/D converter (pin 22 is a logic high signal). VOLUMETRIC relay K4 is also energized. This alarm will automatically reset when the CPU can read the A/D converter again; or b) there is a possible loss of the +10 VDC supply. ERROR CODE 02 A/D read is displayed on the vacuum fluorescent display. 2. There is an A/D converter over range. Possibly caused by: a defective load cell and/or load cell cable; excessive weight on the weigh span; incorrect load cell sense line voltages to pins 14 and 15 of the A/D converter. VOLUMETRIC relay K4 is also energized. This alarm automatically resets when the over range condition is cleared; defective A/D converter (analog front end components). ERROR CODE 01 A/D read is displayed on the vacuum fluorescent display. 3. There is an A/D calibration error. Possibly caused by inconsistent results

during automatic electronic self-calibration of the A/D converter; defective A/D converter; the reference voltage on pins 14 and 15 of the A/D converter is unstable; possible loss of the +10 VDC supply. VOLUMETRIC relay K4 is also energized. This alarm resets when the electronic calibration results are consistent. ERROR CODE 15 A/D calibration error is displayed on the vacuum fluorescent display.

4. There is a Feed Rate error. The demand feed rate has not been met, usually because of an empty belt or partial inlet blockage; or the actual feed rate

5

differs from the demand feed rate by more than 5% for 2000 seconds. This error will reset if the difference falls below the 5% threshold. ERROR CODE 10 Feedrate is displayed on the vacuum fluorescent display.

5. There is an Event Processor Array problem. Possibly caused by failure of frequency outputs to feed back cards or the speed control loop. ERROR CODE 14 EPA watchdog is displayed on the vacuum fluorescent display.

6. The total material integrator data logging pulses have exceeded 5 pulses per second and some pulses are being lost. ERROR CODE 09 Remote TCI is displayed on the vacuum fluorescent display.

7. The primary tachometer signal has not been detected after 3 seconds. ERROR CODE 21 Primary Tachometer Failure is displayed on the vacuum fluorescent display.

8. The CPU could not write data to the EEPROM and then read the same data. ERROR CODE 05 EEPROM write is displayed on the vacuum fluorescent display.

9. The checksum of the data read from the battery backed-up RAM is incorrect, indicating a problem with the data stored in BatRAM. Possible causes are a defective U14 chip, power down sense circuits, or too low of a power loss threshold. ERROR CODE 06 Battery low is displayed on the vacuum fluorescent display.

.

2006-01-28T14:15:17+0530K.K.BASAKCAT-IV

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Gravimetric Feeder