Technical Guide of How to Repair HDL Devices V1.0

8/17/2019 Technical Guide of How to Repair HDL Devices V1.0

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Technical Guide of How to Repair HDL Device V1.0

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Technical Guide of How to Repair HDL Devices

2013-3-01 (V1.0)

Declaration:

a. The maintenance man should have the following skills:

I) Be good at assembling, disassembling and Soldering skills

II) The ability of Electro Circuits Analysis

III) The ability of skilled Operation HDL BUS Pro Set Up Tool

b. The maintenance man should make the maintenance record and periodic summary to improve the skills

c. The necessary Tools: Digital Multi-meter, slotted screw drivers with different sizes, electric soldering iron,

tweezers, solder etc

d. Optional Tools: Digital Oscilloscope

e. Website for more info: www.hdlchina.com

f. Contact info of HDL technical support:

[email protected]

[email protected]

http://www.hdlchina.com/mailto:[email protected]:[email protected]:[email protected]:[email protected]://www.hdlchina.com/


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1. The basic methods of Electro circuits checking

1.1

Electro Circuits Analysis

Make the analysis for the electro circuits first and understand the function of each part, test the voltage and

the wave of each connection point. Know about what phenomenon could be in case of damages exist in

different part of the electro circuits.

1.2

Dichotomy

Check out where is the signal midpoint (For every circuit). Check the signal at the midpoint first, when

abnormal signal appears, check another point which in the middle of those 2 check-points. Keep checking till

the problem point found out.

1.3

Input Standard Signal

Check all points after input a standard signal into the circuits and find out the points where abnormal signal

appears. The standard signal can be input from the midpoint, and 2 direction of the circuit can be checked by

turn.

1.4

Comparison

Alternately check the wave and parameter between a normal PCB and abnormal PCB which has the same

model, under the condition of using same standard tool, check-points and standard signal.

1.5

Replace

Replace the components which damaged or probably damaged after checking. Check the PCB can work as

normal or not after replacement damaged components.

1.6

Other Methods

I) Cant find out where is the problem, please soldering again for the point which not soldered reliable.

II) Wash the PCB first and check it again

III) Check the mainly parameters of each components from www.alldatasheet.com

http://www.alldatasheet.com/http://www.alldatasheet.com/


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2. Instruction of how to use Digital Multi-Meter and Components disassembly

2.1

Introduce of Digital Multi-Meter

Figure 2.1

I) Display screen: value and status will be displayed when it is working.

When the screen shows this value and status, it means over range.

II) Probes:

a. Black Probe: To be connected to the COM plughole on the Multi-Meter

b. Red Probe: To be connected to different plughole on the Multi-Meter:

1. When check the voltage and resistance: connect to the plughole.

2. When check the current which less than 2A: connect to 2A plughole.

3. When check the current which less than 10A: connect to 10A plughole.

III) Measuring Ranges:

a. Use different measuring ranges for different measuring object.

b. The closer between ranges and measured value, the more accurate will be.


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2.2

The Basic usage of Digital Multi-Meter

2.2.1 Warning

a. Please dont check the voltage or current by using the measuring range of resistance

b. Please dont check the voltage by using the measuring range of current

c. Pay attention to the possible electric shock during the checking

2.2.2 Check the Digital Multi-Meter

a. Please dont use a Multi-Meter which has no permitted use notice

b. When the screen shows , please change the battery

c. If the probes of the Multi-Meter are broken, change the probes with a new one

d. Connect the red probe to plughole and connect the black probe to COM, change the measuring

ranges to , touch the 2 probes and listen to the buzzer. It is working fine when hear the sound from the

buzzer.

2.2.3 Measuring the resistance

a. Connect the red probe to plughole and connect the black probe to COM

b. Change the measuring ranges to R

c. Select the correct measuring ranges according to different measuring value:

1) To be measured resistance value: 200K , choose 2M

2.2.4 DC Voltage measurement


b. Change the measuring ranges to


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c. Select the correct measuring ranges according to different measuring value:

1) To be measured voltage:


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Incorrect way of measure correct way of measure

2.2.7 Check the circuit: connect/disconnect



c. When the resistance of circuit less than 50

, the buzzer will make the sound.

2.2.8 Measure the Diode



2.3 Measure the Diode by using the Multi-Meter

Step 3 Step 4


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Step 1: Disassembling the Diode from the PCB

Step 2: Change the measuring ranges to

Step 3: Connect the Red probe to the Positive pole and connect the black probe to the negative pole, the

Screen will have the display of 5xx ! 8xx.

Step 4: Connect the red probe to the negative pole and connect the black probe to the positive pole, the

Screen will show , it means over range.

Step 5: When step 3 and step 4 appears, it means the diode has no problem. Otherwise, means the diode broken.

If the buzzer alarmed during the measuring, it also means the diode has problem.

2.4

Measure the TRAIC by using the Digital Multi-Meter

Step 1: Disassembling the TRAIC from the PCB


Step 3: Measure the TRAIC by following the table:

S/N Red Probe Black Probe Normal Damaged Others

1 A1 A2 Over range Buzzer alarm /

2 A2 A1 Over range Buzzer alarm /

3 G A2 Over range Buzzer alarm /

4 A1 G Buzzer alarm Over range /

5 G A1 Buzzer alarm Over range /


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2.5

Measure the MOC3020 and MOC3052 Optical Coupler

Pin Definition of the MOC3020 and MOC3052, see following picture:

Step 1: Disassembling the Optical Coupler from the PCB


Step 3: Connect Red probe to Pin 1 and connect black probe to Pin 2, the value of the Multi-Meter will show

a value in the range of 5xx ~8xx. See the following picture.

Step 4: Connect the red probe to Pin 2 and black probe to Pin 1, the screen of Multi-Meter will show the over

Range value:

Step 5: If the real measurements are not the same as step 3 and step 4, it means the Optical Coupler has

problem.

If the buzzer alarmed during the step 3 or step 4, it also means the Optical Coupler has problem.

Step 6: Connect the Red probe to Pin 6 and Black Probe to Pin 4:

Ø If the buzzer alarmed during this step, it means the Optical Coupler has problem.

Ø If the screen of Multi-Meter shows over range, it means the Optical Coupler is just working fine.


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2.6

Measure the Capacitance by using the Digital Multi-Meter

First, please disassembling the capacitor from the PCB

2.6.1 A simple J udgment


Step 2: Connect the red probe to the positive pole of the capacitor and black probe to negative pole

Step 3: Listen to the buzzer of the Multi-Meter:

Ø If the buzzer alarmed for a short time, it means the capacitor work fine. The more capacitance is,

The longer alarming will be.

Ø If the buzzer keeps alarming, it means the capacitor has problem. See the following picture.

2.6.2 Accurate measurement

Note: this method is only to be used with the Multi-Meter which has the function of capacitance measure

Step1: Connect the red probe to Cx plughole and black probe to the COM plughole

Step 2: Select the correct measuring ranges according to different measuring value:

Ø If the to be measured capacitance


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Step 3: If the capacitor has polarity, then connect the red probe to positive pole and black probe to the negative

pole. If the capacitor has no polarity, it doesnt matter how to connect.

Step 4: Read the measured value and make the judgment:

Ø If the difference between the measured value and standard value less than 20%, the capacitor is ok.

Ø If the difference between the measured value and standard value more than 20%, the capacitor need

To be replaced.

2.7

Measure the NPN type Triode by using the Digital Multi-Meter

Step 1: Disassembling the triode from the PCB


Step 3: Connect the red probe to pole B and black probe to E, screen shows a value in the range of 5xx~8xx

Step 4: Connect red probe to Pole E and black probe to B, screen shows over range

Step 5: Connect the red probe to pole B and black probe to C, screen shows a value in the range of 5xx~8xx

Step 6: Connect red probe to Pole C and black probe to B, screen shows over range

Step 7: Connect red probe to Pole C and black probe to E, screen shows over range

Step 8: If the real measurements satisfy from step 3 to step 7, it means the triode has no problem. Otherwise, it

Means the triode damaged. If the Buzzer alarmed from step 3 to 7, also means triode damaged.


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2.8

Measure the PNP type Triode by using the Digital Multi-Meter

Step 1: Disassembling the triode from the PCB


Step 3: Connect the red probe to pole E and black probe to B, screen shows a value in the range of 5xx~8xx

Step 4: Connect red probe to Pole B and black probe to E, screen shows over range

Step 5: Connect the red probe to pole C and black probe to B, screen shows a value in the range of 5xx~8xx

Step 6: Connect red probe to Pole B and black probe to C, screen shows over range

Step 7: Connect red probe to Pole C and black probe to E, screen shows over range

Step 8: If the real measurements satisfy from step 3 to step 7, it means the triode has no problem. Otherwise, it

Means the triode damaged. If the Buzzer alarmed from step 3 to 7, also means triode damaged.

2.9

Measure the MOSFET by using the Digital Multi-Meter


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Technical Gui

Note 1: Short circuit theG pole andS pole, t

Note 2: After measurement by Multi-Meter, s

Step 1: Disassembling the MOSFET from th


Step 3: Connect the red probe toS pole of t

Ø If the screen shows a value in b

Ø If the Buzzer alarmed during the

Step 4: Connect the red probe toD pole of t

Ø If the screen shows over range, i


Step 5: Connect the red probe to G (D) pole



Step 6: Connect the red probe to S (D) pole



e of How to Repair HDL Device V1.0

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release the electric charge between the two po

ee the above picture, please release the electric

PCB

e MOSFET and black probe toD pole:

tween 5xx~8xx, it means the MOSFET is ok.

measurement, it means the MOSFET has probl

e MOSFET and black probe to S pole:

it means the MOSFET is ok.


and black probe to D (G), see below picture a:



nd black probe to D (S), see below picture b:



les.

charge too.

m.

m.

m.

m.


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2.10

Measure the Resistor which soldering on PCB by using Digital Multi-Meter

Step 1: Change the measuring ranges to #2M $

Step 2: Connect the red probe to one of the Pin of the resistor and black probe to another Pin.

Step 3: If the screen shows over range, it means the resistor has broken.

2.11 Identification of the resistance

2.11.1 Resistor Color Ring Definition

2.11.2 Surface mounted resistor identification

Resistance Definition Error

Black Brown Red Orange Yellow Green Blue Purple Grey White Gold Silver

0 1 2 3 4 5 6 7 8 9 5% 10%


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2.11.3 Soldering resistor identification

2.12

Disassembling of components

2.12.1 About the Solder:

Ø The solder can be only melted down into liquid status in case of high temperature. It takes time for

the electric soldering iron to reach that temperature.

Ø The component can be only disassembled when the solder turns to liquid status.

Ø Correct way of soldering:

1. move the electric soldering iron close to the Pin of component

2. move the solder close to the iron

3. take away the solder after soldering

4. take away the electric soldering iron

2.12.2 Disassembling of the soldered resistor

One side solder melted down Tweeze one pin first another side solder melted down, tweeze the pin


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2.12.3 Disassembling of surface mounted IC

Step 1: Soldering for the Pins

Before Soldering After Soldering for one side of the IC

Step 2: Uniformly heating for both side of the mounted IC

Ø Single Point heating: melt down the solder by using the electric soldering iron

Ø One side heating: melt down the solder by soldering iron, move the iron on those pins. See !

Ø Two sides heating: meltdown one side solder, move the iron to another side. See "

Step 3: Move away the IC

Move away the IC rapidly when the solder of both sides has been melted down.


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3. How to use the Digital Oscilloscope

3.1

Introduction of Oscilloscope

3.1.1 Front view of a Digital Oscilloscope

3.1.2 Introduction of Oscilloscope Probe

a. Select of Oscilloscope attenuation Knob

Ø Turn around the attenuation knob to X10 position, the signal will be attenuated by 10 times

Ø Turn around the attenuation knob to X1 position, there is no attenuation of the signal.

b. Connect the probe to the signal during the measuring

c. Connect the Ground Spring Clip to the public pin of the signal. See the following picture.


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d. Wiring and connection: see the below picture.

3.1.3 Screen Display of the Digital Oscilloscope


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3.2

Basic Operation

3.2.1 Setting

a. Electric Level deviation adjustment: Turn around the VERTICAL knob, see below picture.

b. Time deviation adjustment: Turn around the HORIZONTAL knob, see below picture.


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c. Trigger Electric Level adjustment: Turn around the TRIGGER knob, see below picture.

d. Setting for multiplying rate on the probe. See below picture.

e. Other setting:

Ø Coupled mode: Direct Current

Ø Trigger type: Edge Trigger

Ø Trigger mode: Auto trigger

Ø Edge type: Rising type

Ø Signal source: CH1

3.2.2 Calibration of Digital Oscilloscope


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a. Follow all the setting of 3.2.1 chapter

b. Connect the probe to the signal output port, see above picture.

c. Set the VOLDIV to 1.00V, set the SECDIV to 1.000ms. See below picture.

d. The screen of Oscilloscope will show the content as the above picture; it means the oscilloscope works

fine. And 1 frame of the signal periodic amplitude will appear, based on the following setting:

Ø Set the calibrating signal to 1 kHz/3V square wave, then 3 frames of the signal amplitude appears.

Ø Set the calibrating signal to 1 kHz/1V square wave, then 1 frame of the signal amplitude appears.

e. If the Oscilloscope is not showing the content in the above picture, it means it has problem.

4. Introduction of typical electric circuits

Note: Different electric circuits will be introduced in the following content, see chapter 6.1 for more info.

Definition of high and low electric level: 1 & means high lever; 0-means low level.

4.1

RS485 interface electric circuit

4.1.1 Electric circuit analysis of RS485 Interface(75176, 3085E or another type)

Ø About the Pin 3 of D1-3085E, enable to send when status is #1$, disable sending when status is #0$


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Ø D1-75176 is to be used for data sending.

Ø Triode V1 is to be used to control the send/receive of the D1, when signal from V1 cut off, and TRC

Set as #1$, in this case the D1 is enabled.

Ø Electrolytic capacitor C1 and resistor R3 consist of the time-delay circuit. When TRC is #1$, after

Time delay, V1 is break over, Point C will be in a status of #0$. Delay time Calculation formula is:

' ( 0.7 ) R3 )C1

Ø VD5 is the circuit for electric charge release channel. The function is to provide a fast channel of electric

charge releasing for the capacitor when TRC is in the status of #0$. When TRC come back to the status

of #1$, and also C1 will not change the delay time.

Ø R5 resistor is the current-limiting resistor when V1 is break over.

Ø The function of diode VD1 is to avoid component burned off in case of wrong power input connection

Ø The functions of diode VD2, VD3 are to limit the input signal amplitude

Ø Description of the whole procedure:

1. When TRC is #1$, C1 will be charged through R3 by Vcc. (Vcc is the power input)

2. When Point B has a electric level of 1.5V, V1 will break over, the level of Pin3 of D1 will be down

3. When TRC is #0$, the charges in C1 will be released through R4, VD5.

4. Below picture is the procedure of C1 electric charge and release:

Charge for C1 Release for C1


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4.1.2 Wave analysis of RS485 Interface

D1 Enable D1 Disable

4.1.3 Function of circuit

Ø CPU to control the send/receive of BUS

Ø To avoid network paralysis when CPU occupied the BUS

Ø To avoid component burned off in case of wrong power input connection

4.1.4 Influence on circuit caused from component failure

Ø D1 will be failure, cant send and receive the data

Ø Capacitance is not enough, sending time will be short, data package cant sent/received completely

Ø Capacitor of C1 cut off, sending time will be short, data package cant sent/received completely

Ø Diode VD5 cut off, cant send and receive data

Ø Resistor R5 cut off, data can be received but cant sent out

Ø Short circuit of diode VD2,VD3, cant send and receive data


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4.2

Trigger electric circuit of TRAIC

4.2.1 Electric circuit analysis

Ø R1 is the current limiting Optical Coupler input resistor

Ø Function of Optical Coupler are trigger signal isolation and bidirectional TRAIC driving

Ø R2 is the bidirectional TRAIC driving ,trigger, current limiting resistor

Ø Resistor R3 and Capacitor C1 are for the output absorption

Ø The function of inductance L1 is to avoid high-order harmonic which generated from the moment of

bidirectional TRAIC output signal

4.2.2 To control a high power by using a small signal


Ø When MOC3020 failure, there is no output, the load will not be turned on

Ø When Bidirectional TRAIC failure, there is 100% output, the load will be turned on fully. See equivalent

circuit below:

Ø When resistors R1\R2 failure, there is no output, the load will not be turned on


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Ø When resistor R3 or capacitor C1 failure, the output will not be reliable.

Ø When inductance L1 failure, the disturbance of output is very high

4.2.4 Others

Ø Generally, if there is no power supply to the device, there is no output signal

Ø If the output is not stable( load will flash), please check the power supply synchronizing signal

Ø Please check the datasheet for the bidirectional TRAIC, opt coupler from the website.

4.3

Power supply electric circuit of RTL34063


Ø It is a BUCK type DC voltage reduction circuit

Ø Inductance L1 and capacitor C4 are consist of the LC Filter circuit

Ø Electrolytic capacitor C4 is to be used as output filter capacitor. Choose the tantalum capacitor can

Effectively reduce the ripple wave

Ø VD2 is diode, usually use a fast recovery on/off diode

Ø R1 is a resistor, for over current measurement. See the below equivalent circuit:

Charge for capacitor Release for capacitor


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4.3.2 Circuit work procedure

Ø When Inner switch tube of RTL34063 is on, the output voltage is rising, under the effect of L1, the

output will be raised linearly.

Ø Switch tube will be turned off when the output value matched the setting value

Ø Inductance L1 and capacitor C4 are discharging to the load, the output voltage fall off linearly

Ø When output voltage is less than setting voltage, the switch tube works

Ø When output voltage is higher than setting voltage, the switch tube will be cut off for protection

Ø Calculation formula of setting output voltage ( select suitable resistor):

Ø Saw tooth wave which has a sequence 24!42kHz is existed in the Pin 3 after the circuit works:

4.3.3 Function of circuit

Ø It is a DC voltage reduction circuit, has the features of wide input range, efficient and low heating

Ø Output voltage can be set

Ø Has the function of over current protection


Ø When Oscillation capacitor failure, the circuit will not work at all

Ø When Resistor R1 failure, the circuit will not work at all

Ø When diode VD2 broken and inductance L1 saturated, ripple wave is existed in the output, to have a

bad influence on other parts of the circuit.

Ø When sampling resistor R2 and R3 failure, the functionality of over current protection is failure, also

capacitor C4 will be damaged.

Ø When inductance L1 failure, the circuit will not work at all.


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Technical Gui

4.4 Switching on/off power supply electric cir

4.4.1 Complete circuit


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cuit


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4.4.2 Mainly circuit

4.4.3 Input part of the circuit

4.4.4 Driving Part of the circuit


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4.4.5 Adjustment part of the circuit

4.4.6 Output part of the circuit

4.4.7 Protection circuit and interior frame of MC3842


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4.4.8 Mainly parameters of MC3842


a. Power supply of the circuit

Ø When Power turn on, the power will be supplied to Pin 7 of UC3842, then the UC3842 will be

powered on after the effect of interior voltage-regulator tube.

Ø When regular work, the power of UC3842 will be supplied from the transformer, the function of VD1 is

the voltage regulating, at last the signal will be filtered by C3 before it goes to UC3842.

b. Adjustment of output voltage

Ø By adjusting the working time of the switch-on/off tube to adjust the output voltage

Ø Feedback transmission part of the circuit. The calculation formula for feedback transmission are the

following:

Iin = Ik +Ii1 ; Ii1 = Ir =Vr / R16 *Vr =2.5V,Standard voltage supplied from TL431.

Vk = Vo - (Ir ) (R14 +R16 )),[ Ir ) (R14 +R16) is a constant value]

Ik = Vk / R13 ; Ifk =Ik ) CTR *CTR is the current transfer ratio of Optical Coupler.

Vfk =Ifk ) R7

So here are the relations: Output voltage0 è Vk 0 è Ik 0 è Ifk 0 è Vfk 0

Output voltage1 è Vk 1 è Ik 1 è Ifk 1 è Vfk 1


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Feedback Transmission Part Interior Structure of TL431

c. Process of Voltage Adjustment

Ø Feedback voltage will be reverse direction amplified after it goes to the error amplifier, and it

becomes the error voltage which is one third of the voltage.

Ø The comparison of the error voltage and current. (See below picture)

If the current >error voltage, it will generate high level, and reset the PWM latch

If the current


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Ø Adjustable Loop

Output voltage0 22 >Error Voltage 1 22 >PWM Pulse Width1 22 >Output Voltage1

Output voltage1 22 >Error Voltage 0 22 >PWM Pulse Width0 22 >Output Voltage0

d. Functionality of each component during the adjustment

Ø VT1 is the voltage reference (Standard voltage for comparison)

Ø B1 is the feedback isolation transmission

Ø R5,R6 and C7 are consist of feedback loop of the UC3842 Interior Error Amplifier

Ø R2 and C5 work together with the interior oscillation circuit of UC3842

Ø VD1, C8 and C9 supply the power to UC3842 after power supply normally

Ø R1 supply the power to UC3842 when power on the device

e. The drive of switching tube

Ø This circuit is a double tubes Flyback type power supply circuit. The 2 switching tubes work at the

same time for open/close. When the switching tube is closed, the Peak Reverse Voltage will be

absorbed by the diode and switching tube.

Ø There is a big difference of voltage between the V3 and the high power line public port, the difference

is even higher than the driving voltage of UC3842. So T2 is to be used as the floating drive of the V3.

And V1, VD2 and VD3 consist of one circuit to speed up the V3 switching on/off time.

Ø C10 is the isolation for T2, R3 is current limiting unit.

Ø R8 and R9 can reduce the input impedance of V3, to reduce the interfering.

Ø R11and R12 can reduce the input impedance of V4, to reduce the interfering.

Ø Z1 and Z2 are used to limit the amplitude, to protect the switching tube.

f. Over Current protection

Ø #I$ is the working current of switching tube. After the current goes to R10, it will has voltage drop of

Ucs =I ) R10


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Ø Ucs goes to UC3842 after R4/C6 filter circuit, to be compared with the interior threshold value 1V.

see the below picture.

If the Ucs >threshold value Uthr, output in Pin6 will cut off

If the Ucs Uthr, in this case the switching tube will cut off and there is no output in Pin6.

Ø Lower Voltage Protection:

When the input voltage of UC3842 is very low, less than 16V, the interior low voltage comparator will

send out a low electro level. About the low voltage comparator, please see the above picture, there is

a AND gate which is used for the low voltage comparison. If the input voltage is higher than 16V, the

output will come back to normal.

g. Output

Ø Switch transformer secondary winding induction electromotive voltage will be adjusted by VD6. And

then it will be filtered by the #3$ type filter circuit which consists of C124L24C16

Ø There will be a LED indicator for the output status

Ø F2 is the over current protection part of the output

Ø VD7 is the parallel connection of the output

Ø R18 is the terminal resistor of the RS485 BUS


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S/N Component Normal Failure Phenomenon

01 Load Short Circuit 5678

02 F1 Open circuit C3 has no 300V DC Voltage

03 RT1 Open circuit C3 has no 300V DC Voltage

04 C3 Breakdown Input circuit burned off

05 R1 Open circuit UC3842 not working

06 VD1 Open circuit UC3842 not working

07 R24C5 Open circuit UC3842 not working

08 T19Primary Winding interturn short circuit Over current protection

09 T19Primary Winding Open circuit No Output

10 T29Primary Winding Open circuit No Output

11 R10 Open circuit No Output

12 C134C16 Capacitance reduce Output ripple wave raised

13 R144R16 Resistance changes Output voltage changes

14 F2 Open circuit No output, indicator turns on

15 VT1 damaged*Standard Voltage is not 2.5V. Output voltage changes

16 B1 Primary Open No Output

17 V34V4 Open circuit No Output

18 VD6 Open circuit No Output

Others9

1. When short circuit in load, power supply is cut off. Power will come back after disconnect the load.

2. If V34V44R10 damaged, usually it is open circuit, sometimes because of burned off.

3. When checking the T14 T2, recommend to disassembling it from PCB.

4. When checking T2,recommend to check if the C10 is breakdown or burned off.

5. When checking V34V44VD6,recommend to check if the contact between the radiator.

6. If C3 damaged,U14RT1 must be replaced.


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4.5

MOSFET Dimming Circuit

4.5.1 Complete circuit. (See below picture, take 2 channel Dimmer as an example)


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4.5.2 Mainly Circuit

Working in Positive Half-circle Working in Negative Half-circle


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4.5.3 Zero-crossing detection circuit

4.5.4 Input Part of the circuit

4.5.5 Modular Part of the circuit


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4.5.6 IR2127 interior frame


a. Working of mainly circuit:

Ø reference to the chapter of 4.5.1

Ø Working in Positive Half-circle: Lè N2 è R11 è R12 è N3*diode. è load è N

Ø Working in Negative Half-circle: Nè load è N3è R12è R11 è N2*diode. è L

b. Power supply of the modular

Ø Use the method of half wave and commutate to lower down the voltage. 1VD3 is to be used as the

commutate, while 1R11, 1Z2 to be used for preliminary voltage lower down method, to lower the

voltage from 220V to 30V.

Ø 1R10 and 1Z1 are to be used for the secondary voltage lower down method, to lower the voltage

from 30V to 15V.

Ø Due to the fact that most of the power consumption during the voltage lower down will be sustained

on the 1R11, so the 1R11 can be damaged very easily in case that the input voltage is very high.


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c. Drive

Ø Please refer to the chapter of 4.5.6, the interior frame of the IR2127.

Ø Process of triggering signal

1. The trigger signal will be input to a Schmitt Trigger in IR2127, to be used to generate a PULSE,

see ;

2. The trigger pulse goes to D-trigger, the output of the D-Trigger will be #0$, low level, see .

Ø Protection

1. Low voltage protection: when the voltage of Vb is less than 12V, will have a RESET

level, to make sure that output of D-Trigger is low level voltage-#0$, see ?

2. Over current protection: When the output of the IR2127 is high level voltage, the signal of current

detection Vcs will be transferred to the current detect comparator, to be compared with the

built-in standard 250mV voltage, see @. When the Vcs is higher than 250mV,the comparator will

have a output of a SET signal, and meantime, over current protection trigger will have a output of

so called protection high level voltage. The signal of protection high level voltage and the trigger

signal will be transferred to a logic gate of AND, to make sure the output of the trigger is a low

level voltage. And the protection high level voltage will be transferred to the feedback output

trigger. (see A) The output of the feedback output trigger will have a output of FAULT signal.

Ø Zero Crossing detection

1. The functions of Transformer T1 are isolation and transmission. The input voltage will be

transferred into AC Current. It will be transferred into AC Voltage by using the R2. R3 and R6 are

consists of the polarization of comparator input signal.


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Ø The causing of the zero crossing signal

1. When the power supply voltage is under the positive half period, the voltage in P is higher than

voltage in N. the output of the comparator will have a output of high level voltage-#1$

2. When the power supply voltage is under the negative half period, the voltage in P is lower than

voltage in N. the output of the comparator will have a output of low level voltage-#0$

3. The zero crossing signals will be transferred to the CPU for processing:

1) CPU will send a command to break over MOSFET tube when it is exactly the time for zero

crossing, to start the timer.

2) CPU read the break over time of the MOSFET, to compare it with the standard time.

3) CPU will send a command to cut off the MOSFET in case of equivalent.

Ø Mainly parameters for IR2127


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Ø Influence on circuit caused from component failure

S/N Components Normal damages Phenomenon

01 Load Over range Over current, not working

02 R1 Cut off No zero-crossing signal, not working

03 1R11 Cut off No power, not working

04 1B2 Damaged Trigger signal cant be transferred

05 1R24R1841B1 Damaged Feedback error, not working

06 F1 Cut off No output

07 R13!R14 Cut off No output

08 N24N3 Cut off No output

09 1U1 Damaged No output

10 N24N3 One of them short circuit/ Cut off flashing

11 R3!R8 Resistance error, soldering unreliable flashing

12 N24N3 short circuit Load will be turned on always

others9

Here is the example of one channel when components failure,2ch44ch can be solved accordingly


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5. Check the circuit by using the Digital Multi-Meter and Digital Oscilloscope

5.1 Preparation work

5.1.1 Preliminary analysis

1. Ask

Ø Ask the user, the phenomenon when the problem happens, and ask if any setting changed before the

problem happens. Ask the user, if any default setting of the device itself has been changed or not.

Ø Ask the user the working condition and power supply of the device

Ø Ask the user if there is any action of plug-in/out when the device connected to the power

Ø Ask the user if there is any maintenance has been done to the device

2. Setting

Ø Check the setting of the device, make sure every setting is correct

Ø If there is any mistake on the setting, please change it to a correct setting

3. Observation

Ø The fuse - if it is burned or not

Ø The components & any damages, any soldering unreliable, burned etc

Ø The circuit on PCB & burned, short circuit, any damages etc

Ø The plug in/out unit & connection unreliable, value of resistance, capacitor, inductance correct or not

Ø PCB Board & burned, if any deformation etc

Ø Quality of soldering & short circuit, unreliable etc

4. Smell

Ø To find out any places on the PCB board has the smelling of anxious burnt flavor

5. Others: the defect unit will have a bad influence on the system, please uninstall it from the BUS

and repair it.


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5.1.2 It is very important to aware the high power part of the whole circuit.

5.1.3 Remove the Ground Plug of the power connector of the Digital Oscilloscope

5.1.4 Calibration of the Digital Oscilloscope, see chapter of 3.2.2

5.2Check the Trigger circuit of the TRAIC

Be Aware of the electric shock of the Trigger circuit of TRAIC

Uncertified maintenance man is not allowed to check.

5.2.1 Preparation work before checking

Ø Make the record of what actual phenomenon

Ø Check the cabling and wiring, the patching, setting of high/low threshold in output

Ø Check the load, replace it in case of broken

Ø Check the Fuse and protection switch in the output of the device

Ø Check the synchronization signal of the power supply


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5.2.2 Check the TRAIC and Optical Coupler (OC) after power disconnected

Ø Observe the phenomenon, if there is full output, means the load always turn on, please check the

TRAIC in first priority

Ø Disconnect the power of the device

Ø Follow the chapter of 2.4 to check the TRAIC and follow the chapter 2.5 to check the OC

5.2.3 Check the Optical Coupler MOC3020 after power disconnected

Ø Observe the phenomenon, if there is no output, means the load always off, please check the OC in

first priority

Ø Disconnect the power of the device

Ø Follow the chapter 2.5 to check the OC

5.2.4 Check the Trigger signal by using the Digital Multi-Meter

Ø Change the measuring ranges to , , it is the range of 20V

Ø Connect the red probe to TRIG pin, black probe to GND pin, see below picture:

Ø Turn on the power supply of the device, set up the output in the related channel

Ø The display of the multi-meter should be 0.00V!4.5V, the more the output, the more the measure

value will be.

l Match the above reference: Trigger signal is normal. Please check the R1\R2, OC and TRAIC

l Do not match the above reference: trigger signal not working. Please check the pre-circuit.


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5.2.5 Check the Trigger signal by using the Digital Oscilloscope

Ø Set the value as 50% in the output of the channel which is to be measured, please follow the above

picture for the operation. If everything right, rectangle wave which has 10ms period will be displayed

on the screen of the Oscilloscope. If the phenomenon is not matching the above reference, there is

no trigger signal input, please check the pre-circuit. The setting of the oscilloscope is:

5.3 Check the RTL34063 power supply circuit

5.3.1 Check the power supply input

Ø Disconnect the power supply of the device

Ø Measure the input voltage of the by using the digital Multi-Meter

Ø The power supply circuit might be damaged if there is a voltage more than 40V

Ø If the voltage is lower than 6V, the power supply has problem and should be replaced


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5.3.2 Check the voltage of the power supply

Ø Connect the power to the device

Ø Change the measuring ranges to , , it is the range of 200V

Ø Measure the voltage according to the above picture

Ø If the voltage is lower than 5V, the power supply has problem and should be replaced

5.3.3 Check the current of load

Ø Disassembling the inductance in the circuit

Ø Set the DC Power outputs is 5V; connect the output public clip to the GND Pin2 see above picture.

Ø Change the measuring ranges to #2A$

Ø Connect the red probe to 2A plughole and black probe to COM plughole on the Multi-Meter.


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Ø Connect the red probe to DC Power 5V output; connect the black probe to the output of the circuit.

See above picture.

Ø Measure the load current according to the above picture

Ø If the measured current is more than 1.5A, this value is not the designed value, it has problem.

Ø If there is over current of the load:

l Cause the damage of the circuit

l Cause the protection of the circuit, there will be no output

Ø In case of over current in load, please check the load current first and make sure the load current

under the correct range, then the whole circuit can be checked accordingly.

Ø If there is no DC power voltage stabilization, you can disconnect the output of the circuit, and then

series connect a multi-meter to the circuit. See below picture.

5.3.4 Check the components

Ø Change the measuring ranges to

Ø Check the resistor of R1, if the buzzer not ring, the resistor broken

Ø Check the Pin 1 and Pin 2 of the integrated block, if the buzzer rings and also the measured

resistance is less than 5B,RTL34063 broken.

Ø Check the diode VD2, if the buzzer keeps ringing, the VD2 broken.

Ø Check the inductance L1, if the buzzer not ring, the inductance broken.


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5.3.5 Check the feedback circuit

Ø Change the measuring ranges to

Ø Disconnect the power, connect the red probe to the Pin 5 of N1, connect the black probe to R24R3

midpoint. See above picture.

Ø If the buzzer of the multi-meter rings, the circuit works fine, otherwise the circuit has problem.

Ø Others:

l If the feedback circuit has problem, the defect channel will be out of control. All the interior

switching tubes of RTL34063 will be switched on and all power input will be transferred directly

to C4 and load, in this case the C4 capacitor will be damaged. Because the over current

protection of the RTL34063 will not have enough time to react when this happened.

5.3.6 Check the RTL34063 by using the Digital Oscilloscope


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Ø Follow the operation of the above picture, check the Pin 3 of RTL34063, in the screen there will be a

sawtooth wave which has a frequency of 24kHz ! 42kHz. The setting of the oscilloscope is:

5.4Check the RS485 Circuit

5.4.1 Understand the phenomenon and make the record

Ø Cant send and receive data, check the VD24VD3 and D1

Ø Can receive but cant send

Ø Has a limitation to send data package, check the R34C1

Ø Can send the data package for a long time, check the V14VD4

5.4.2 Set up a system for checking

Ø Follow the above picture for the Hardware connection

Ø Install a HDL BUS Pro Set Up tool which has a version higher than V10.17.09


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Ø Please apply for the software license from HDL Technical support if it is first time of installation

Ø Please make sure the wiring is correct and follow the HDL BUS RS485 definition

Ø Please connect the power supply module into the system

5.4.3 To do the maintenance assisted by the HDL BUS Pro Set up Tool

Ø Go to the command test interface: Software >Tool >Command Test:

Ø Start the continues search: This is to be used for helping to check the receiving BUS signal

Ø Input the ID information of the IP Interface


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Ø Input the command

Ø Click #Start$ to start the command test


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5.4.4 The Checking in case of receive/send failure

Ø Follow the below picture during the checking

Ø Check if there is short circuit of VD24VD3, please replace it if it has problem

Ø If VD24VD3 has no problem, then please check the circuit gain after replace D1

5.4.5 The Checking in case of can only receive while send failure

Ø Follow the below picture during the checking, check the R4 and VD5. The green marked components

in the below picture has to be checked.

Ø According to the picture we know that when R4 or VD5 are cut off, the electric charges from C1 cant

be released through R4 - VD4 when TRC has a low level voltage-#0$. On other side, C1 will be

charged through R3, to keep itself in a high level voltage-#1$.

Ø If C1 keeps in a high level voltage-#1$, and then V1 keeps in a working status. The level of Pin3 of D1

will be kept in a low level-#0$ influenced by V1, this will disable the sending.

Ø When the CE Pole of V1 breakdown, this will cause a low level-#0$, and disable the sending of D1.


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Ø Summary: Check the R4 and VD5 first. Check the CE pole of V1 to see if it is breakdown.

5.4.6 The Checking when there is limits of sending long data package

Ø Check the R3 and C1

Ø According to the delay time formula' ( 0.7 ) R3 )C1, so when the capacitance of C1 falls, the time

will be shorter. This causes the influence when sending a data package.

Ø Follow the chapter of 2.6 to measure the capacitance of C1

5.4.7 The checking when data package ban by sent for long time

Ø Follow the below picture during the checking:

Ø Check the V1, to see if it is cut off. If it is cut off, D1 cant stop the sending.

Ø Check the VD4, to see if it is cut off.

Ø Check the C1, to see if it is short circuit.

5.4.8 The checking of signal receiving by using Digital Oscilloscope


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Ø Follow the chapter of 5.4.2 to build up a system

Ø Run the HDL BUS Pro Set tool in PC

Ø Search the device by using the HDL BUS Pro Set tool, see chapter 5.4.2 and 5.4.3

Ø Check the signal according to the above picture.

Ø Setting Time interval for searching:

Ø If there is no signal, please check the 75176 and pre-circuit

Ø The setting of Digital Oscilloscope is:

5.5 Check the Power Supply Module

*Be Aware of the electric shock of the 300V high voltage

*Uncertified maintenance man is not allowed to check.

* Better use *Better use an isolated transformer to avoid electric shock

The high power part of the Module is:


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5.5.1 Consideration on safety

Ø Be careful of personal safety when checking the circuit in case the power connected

Ø Pay attention When check the high power which in the above picture:

1. Check if there is remaining voltage after power supply disconnected. There is a 300V voltage

between the 2 ports of the filter capacitor, due to the fact that electro charges remains after

switching tube stopped working. So the voltage of filter capacitor must be checked in a first

priority. If there is high power voltage, please release the voltage.

2. To avoid short circuit due to the fact of circuit failure, please connect a 100W lamp series into the

circuit, to limit the current of the whole circuit.

5.5.2 Make record about the condition when power supply failures

Ø The condition of output

1. No output at all

2. Has interval when output

3. The output voltage falls down when connect a Load to the power supply

Ø The condition of load

1. Working fine without load, stop work when load connected

2. Disconnect parts of the total loads, power supply module works fine

Ø The condition of failure

1. The indicates of the LED indicator flashing and has interval of on/off

2. Components failure, burned, flavor, out of shape, etc


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Ø Make the Record:

1. Record the condition of output and load

2. Record the condition of LED indicator

3. Record the failure components, the name, types etc.

5.5.3 Measure the electrolytic capacitor C3 by Digital Multi-Meter

Ø Change the measuring ranges to , it is 200V range.

Ø Disconnect the power, connect the red probe to positive pole of C3, black probe to negative pole

Ø If the screen displayed over range, it means the C3 has high power.

5.5.4 Electro charges release for C3

Ø Choose a load (lamp) which has power more than 100W

Ø Soldering two probes on the lamp in a safety way

Ø Connect the lamp to the positive and negative poles of the C3

Ø The lamp will be turned on firstly, wait until the lamp turned off. There is no charges anymore.


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5.5.5 Check the mainly components

Ø Check the fuse F1

1. Change the measuring ranges to , connect the red/black probes to two ports of the fuse.

2. If the buzzer rings, the fuse is ok. If the buzzer not rings, the fuse broken.

Ø Check the thermistor RT1

1. Change the measuring ranges to , connect the red/black probes to two ports of the fuse

2. If the buzzer rings, the fuse is ok. If the buzzer not rings, the fuse broken.

Ø Check the MOSFET tube

1. Change the measuring ranges to

2. Connect the red probe to the S pole of MOSFET, and black probe to D pole. If the buzzer rings, it

means the MOSFET tube broken.

Ø Check the integrated Block of UC3842

1. Please follow the chapter of 4.4

Ø Check the signal isolated transformer: the same method of checking T1

5.5.6 Check the oscillation of UC3842


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Ø Connect the Oscilloscope Ground Line to the circuit as the above picture, turn on the power

Ø Check the Pin 4 of UC3842, on the screen there is sawtooth wave which has a frequency of 40kHz C

2kHz.

Ø If there is no wave on the screen, or the wave has different frequency, the UC3842 has problem

Ø In that case, please check the R2, C5 and also the wiring

Ø The calculation formula for frequency is: f ( 1.8 / (R2 ) C5)

Ø The settings of Oscilloscope are:

5.5.7 J udgment of over current protection

Ø See above picture. Connect a load to the output and turn on the power supply

Ø Measure the input voltage of UC3842

Ø If the voltage is less than 16V, the UC3842 protected in condition of low voltage

Ø In above picture, if the lamp keeps on, means there is no problem.

5.5.8 J udgment of low voltage protection


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Ø Change the measuring ranges to , the range of 20V

Ø Connect the power to the power supply

Ø Measure the input voltage of UC3842

Ø If the voltage is less than 10V, the power supply module protected in condition of low voltage

Ø If the voltage is less than 16V, the power supply module protected in condition of low voltage and

also there will be no response from the power supply

5.5.9 Power supply protected and no output due to a fact of large load connected

Ø Check the power supply follow chapter 5.5.6, in case the power supply has no problem

Ø In the maintenance report the power supply failure and no output

Ø Initial J udgment: the power supply is ok but it has no output because the load is too large.

Ø Suggestion: connect more power supply modules into the system.

5.5.10 Check the working conditions of TL431


Ø Connect the red probe to the regulator Pin of TL431, black probe to the GND port. See below picture.


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Ø Turn on the power and read the measured voltage value

Ø If the measured value is in the range of 2.5V C 0.5V, the TL431 works fine

5.5.11 Check the signal drive circuit of the switching tube V3

Ø Disconnect the connection between R3 and Pin 6 of UC3842


Ø Connect the red probe to Negative pole of Z1, black probe to Positive pole of Z1, see below picture.

Ø DC Power supply:

1. Output voltage is 12V

2. Connect a Red probe to the Positive pole of the DC Power Supply

3. Connect the output public port to the #SOV$ in the circuit

Ø Touch the R3 by using the red probe which connected to the positive pole of DC power

Ø Read the value of voltage:

1. If the voltage is higher than 10V, the signal drive circuit has no problem.

2. If there is no voltage measured, the signal drive circuit failure.


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5.6 Check the MOSFET Dimmer

* Be Aware of the electric shock of the High voltage circuit.

* Uncertified maintenance man is not allowed to check.

* Better use an isolated transformer to avoid electric shock

The high power part of the Module is:

5.6.1 Consideration on Safety

Ø Be careful of personal safety when checking the circuit in case the power connected

Ø Pay attention When check the high power which in the above picture:

5.6.2 Make record about the conditions when failure


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Ø The setting of the module in the software

Ø If there is flashing of the load, check the synchronizing signal

Ø No output, check the fuse

Ø No output, check the mainly components

Ø No output, there is over load protection

Ø No output, the interior power supply damaged

Ø No output, MOSFET damaged

5.6.3 Checking when under condition of over load

Ø Turn on the power of the Dimmer, set up 100% output on channel 1 and channel 2

Ø Choose a typical lamp which is 100W or 200W

Ø Soldering cables on the lamp, there are clips in the terminal of the cables

Ø Connect the clips to the Pin 1 and Pin 3 of XS3, see below picture.

1. The lamp keeps on: the circuit has no problem; the load was too large for the circuit.

2. The lamp is not turned on, the circuit has problem. Check channel 2 in the same method.

5.6.4 Turn off the power; check the related power component by using Digital Multi-Meter

Ø Check the fuse F1 follow the chapter of 5.5.5

Ø Check the MOSFET of N24N34N44N5 follow the chapter of 2.8

Ø Check the L1:


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1. Change the measuring ranges to

2. Connect the red/black probes to A1/A2, and then connect the red/black probes to B1/B2

3. If the buzzer rings under above 2 conditions, L1 has no problem

4. If the buzzer falls to ring under any one of the above 2 conditions, the L1 damaged

Ø Check the thermal resistor of RV14RV24RV44RV5 follow the chapter of 5.5.5

Ø Check the resistor of R11!R144R15!R18

5.6.5 Turn off the power and check the module by using the Digital Multi-Meter

Ø Check the 1R1142R11 follow the chapter of 2.9

Ø Check the 1R242R2 follow the chapter of 2.9

Ø Check the Optical Coupler of 1B242B2 follow the chapter of 2.5

5.6.6 Check the input part by using the Digital Multi-Meter

Ø Change the measuring ranges to #AC2000V$

Ø Connect the red/black probes to the two ports of L1, see below picture.

Ø If there is measured value of 180V ! 250V displayed on screen, the input part has no problem


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5.6.7 Turn on the power of the Dimmer, and check the voltage in different points

Ø Check the MOSFET in case there is no output. See above picture.

Ø Set up there is 50% in the output, and change the measuring ranges of the Multi-Meter to DC200V

Ø Measure the voltage by turns:

1. Measure the Point 1 & should be DC30V, if it is lower than 30V, the module will not work

2. Measure the Point 2 & should be DC12V, if it is lower than 12V, the module will not work

3. Measure the point 3 & should be DC6~8V, if not, the trigger signal is not transferred. Please

check the 1B241R8 and also control board.

4. Measure the Point 4 & under working condition, the voltage should be less than 250mV, if it is

higher than 250mV, there is no output due to the over current protection. Please check the R11!

R14.

5. Measure the point 5 & under working condition, the status of this point should be a low level #0$, if

it is high level #1$, the CPU in control board will send out a command to stop the output. Please

check the Optical Coupler 1B1.


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5.6.8 Check the Zero Crossing signal by using the Digital Oscilloscope

Ø See below picture when checking the signal

Ø The setting of Digital Oscilloscope are:

Ø The checking of the waves:

1. Check if there is sine wave. If not, please check the pre-circuit.

2. Check if there is signal changes on the zero crossing point, if not, please check resistor

3. Check if there is synchronization on pulse signal. If not, replace the comparator.


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5.6.9 Check the trigger signal by using the Digital Multi-Meter and Oscilloscope

Ø Check the trigger signal by using the Digital Oscilloscope

1. Set up a 50% output, follow the above picture. There will be a sawtooth wave which has a 10ms

period.

2. Regulate the output, the duty cycle of the sawtooth wave changes.

3. Check the signal of the low power voltage port, if there is signal, and then please check the signal

of high power voltage port.

4. If there is no sawtooth wave in the low power voltage port: there is no signal input to the trigger

circuit. Please check the pre-circuit.

5. If there is no sawtooth wave in the high power voltage port: Please check the power module,

Optical Coupler and resistor of 1R841R11 etc.

6. Note: the signal between low power voltage port and the high power voltage port is different.

Ø The settings of the Oscilloscope are:


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Ø Check the trigger signal by using the Digital Multi-Meter

1. Set up a 50% output.

2. Measure the voltage as the above picture, if it shows a value between 1.3V ! 2.0V, the trigger

signal has no problem.

3. Change the measuring ranges to #DC20V$

4. Connect the red probe to Pin 3 and black probe to Pin 1, see above picture.

5. The multi-meter will show a value in the range of 1.2V ! 1.6V

6. Regulate the output in channel: Brightness 0è Voltage 1 ; Brightness 1è Voltage0

7. If it is not matching the above description, means there is no trigger signal. Check the pre-circuit

8. Check the signal of the low power voltage port, if there is signal, and then please check the signal

of high power voltage port.

9. Connect the red probe to Pin 2 of 1U1 and black probe to MOV port. See below picture.


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Technical Gui

10. This time the screen will sho

11. Regulate the output in chan

12. If it is not matching the abov

6 Appendixes

6.1 Symbols for components

Components Symb

Resistor

High Power Resistor

Piezo resistor

Optical Coupler

MOSFET

Conjugate Filter

Fuse


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w a value in between #6.9V ! 7.8V$

el: Brightness 0è Voltage 0; Brightness 1è

description, there is no trigger signal. Check th

ls Pictures

oltage1

e Optical Coupler


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Technical Gui


Components Symbo

Bridge Rectifiers

PNP triode

NPN triode

Inductance

Amplifier/Comparator

Transformer

Voltage Standard


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ls Picture


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Components Symbols Picture

TRIAC

voltage stabilizing diode

Diode

Capacitor

Electrolytic capacitor

Electrolytic capacitor

Adjustable Resistor

Light-emitting diode

6.4 Normal failures

Components Phenomenon of failure How to deal with

TRIAC Short circuit or cut off Replace

Switch tube short circuit Replace

High power Resistor cut off Replace

PLCC Socket Contacts of connection unreliable Re-connect

PowerSupply No oscillation Check

Documents

Technical Guide of How to Repair HDL Devices V1.0