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H&B ApS
MODEL DAS 72.1 MANUALDIGITAL LOAD CELL AMPLIFIER WITH ANALOGUE OUTPUT AND SETPOINTS
Tel : +49 (0)2721/9262-0 Fax: +49 (0)2721/9262-50
www.soemer.de
Tel : +44 (0)1446 771185 Fax: +44 (0)1446 771186
Tel : +45 4816 0880 Fax: +45 4816 0870
www.sensortechniques.com www.haubac.com
Ideen & Meßtechnik
TECHNIQUES LIMITED
Ideas in Measuring ..
Page 1 DAS72.1 Manual Issue1c
Rel. 2Rel. 1Net
Digital Amplifier + Setpoint DAS 72.1 Made in EU by DenmarkH&B
+ + + + ++ + +Gnd
2-20mA 12-24Vdc
Io- - - - - 000NC NCNO NO
Exc Sen Sig Sig Sen Exc Rx Rx Tx Tx
Load cell 10V 330Hz Relay 1 Relay 2RS422/485 Input 1 Input 2 PWRCL out
SET UP
1.Zero1.0/allow>0<2.Calibrate3.Set mV/V4.LC tst.Vdc
2.Span1.Set cal ´n´2.Calibrate3.Set mV/V4.Disp.mV/V
3.Display1.Upp.lim.´n´2.Low lim.´n´3.Step*´n´4.Dec.point
4.Filter1.fcut Hz2.Jump >´n´3.Z.Motion´n´4.T.Motion´n´
5.CLout1.4mA=´n´2.20mA=´n´3.Base4.Test I mA
6.Relay11.SPoint´n´2.Hyst.+/-´n´3.Base4.Test
7.Relay21.SPoint´n´2.Hyst.+/-´n´3.Base4.Test
8.Datacom.1.Baud rate2.422/4853.Address4.Auto trns.
TTT0T
Inp.1 Inp.2
CONTENTS DAS72.1
Page 2 DAS72.1 Manual Issue1c
Wiring Diagram and Key Functions Page 3
Quick Setup and Calibration using Weights Page 4Quick Setup and Calibration using the load cell mV/V Sensitivities Page 5
Setup and calibrate Zero Function / Switch load cell excitation to 10VDC (Test Mode) Page 6Setup and calibrate the Span Function / Display Input Signal in mV/V Page 7 Setup the Display Page 8Filter Setting and No Motion Page 9Analogue Output (4-20mA) Settings Page 10Relay1 Settings (Setpoint 1) Page 11Relay 2 Settings (Setpoint 2) Page 12
Data Communication Settings Page 13
Error Codes / Return to Factory Settings Page 14
Communication Protocol Page 15
ExamplesCalibration Procedure using weights Page 16Calibration Procedure from known load cell mV/V sensitivities - Multiple active load cells Page 17
Single active load cell plus pivot Page 18
- S
IGN
AL
SH
IEL
D
- E
XC
ITA
TIO
N
- S
EN
SE
+ E
XC
ITA
TIO
N
+ S
EN
SE
+S
IGN
AL
Load cell connections
12-24 VDC
4-20mA Output
No
rma
lly C
lose
d C
on
tact
Co
mm
on
Co
nta
ct
No
rma
lly O
pe
n C
on
tact
Lo
gic
In
pu
t 1
(+
)Re
ceiv
e +
Re
ceiv
e -
Tra
nsm
it +
Tra
nsm
it -
Gro
un
d
Lo
gic
In
pu
t 1
(0
V)
Lo
gic
In
pu
t 2
(+
)
Lo
gic
In
pu
t 2
(0
V)
No
rma
lly C
lose
d C
on
tact
Co
mm
on
Co
nta
ct
No
rma
lly O
pe
n C
on
tact
Relays Inputs Logic Inputs
RS422/485 Comms.
Recessed Enable Switch(Enables changes to be made to important parameters. Must be pressed before attempting to change parameters 1.1 to 1.3, 2.1 to 2.3 and 3.1 to 3.4)
Relay 2 active
Relay 1 active
Unit in Net Mode
Up Key
Down Key
Press either Key for morethan 3 seconds to enter the ‘Set up’ Mode
Zero Key - Sets new zero (if enabled). Reverts to calibrated zero if the button is held down for more than 3 seconds. Switches unit back to ‘Gross’ mode if a tare has been set. Acts as the ‘Enter’ key in the ‘Set-up’ Mode.
Tare Key - Puts unit into ‘Net’ mode. When inside ‘Set-up’ Menu this key moves the menu back one step. Also moves ‘Digit Selected’ to the right inside sub menus.
‘Set-up’ menu structure
DAS72.1
Page 3 DAS72.1 Manual Issue1c
Rel. 2Rel. 1Net
Digital Amplifier + Setpoint DAS 72.1 Made in EU by DenmarkH&B
+ + + + ++ + +Gnd
2-20mA 12-24Vdc
Io- - - - - 000NC NCNO NO
Exc Sen Sig Sig Sen Exc Rx Rx Tx Tx
Load cell 10V 330Hz Relay 1 Relay 2RS422/485 Input 1 Input 2 PWRCL out
SET UP
1.Zero1.0/allow>0<2.Calibrate3.Set mV/V4.LC tst.Vdc
2.Span1.Set cal ´n´2.Calibrate3.Set mV/V4.Disp.mV/V
3.Display1.Upp.lim.´n´2.Low lim.´n´3.Step*´n´4.Dec.point
4.Filter1.fcut Hz2.Jump >´n´3.Z.Motion´n´4.T.Motion´n´
5.CLout1.4mA=´n´2.20mA=´n´3.Base4.Test I mA
6.Relay11.SPoint´n´2.Hyst.+/-´n´3.Base4.Test
7.Relay21.SPoint´n´2.Hyst.+/-´n´3.Base4.Test
8.Datacom.1.Baud rate2.422/4853.Address4.Auto trns.
TTT0T
Inp.1 Inp.2
Page 4 DAS72.1 Manual Issue1c
QUICK SET UP AND CALIBRATION USING WEIGHTS
Press the UP or DOWN key for more than 3 seconds to enter the Set-up MenuSET UP
0T
Inp.1 SET THE DISPLAY UPPER LIMIT. (MAXIMUM VALUE +99,999)Use the UP/DOWN & MOVE RIGHT keys to set the maximum display value required.
0T
Inp.1 SET THE DISPLAY LOWER LIMIT. (MINIMUM VALUE -9,999)Use the UP/DOWN & MOVE RIGHT keys to set the minimum display value required.
SET THE DISPLAY STEP SIZE. (1, 2, 5, 10, 20, 50, 100, 200, 500)Use the UP or DOWN key to set the required display step size.
0T
Inp.1
CALIBRATE THE ZERO POINT.(CONVENTIONAL WEIGHING SYSTEM)Display shows the actual input signal in mV/V. Press the Enter key to store the zero.
0T
Inp.1
0T
Inp.1 SET THE SPAN CALIBRATION VALUE.Use the UP/DOWN & MOVE RIGHT keys to set the display value equivalent to the calibration weight or the calculated mV/V signal derived from the load cell(s) test data.
CALIBRATE THE SPAN. (CONVENTIONAL WEIGHING SYSTEM)Display shows the actual input signal in mV/V. Apply test weights equivalent to the calibration value set in section 2.1. Press the Enter key to store the new span value.
0T
Inp.1
SET THE DECIMAL POINT POSITION (0, 0.0, 0.00, 0.000, 0.0000)Use the UP or DOWN key to set the required decimal point position. Please note that with 4 decimal places set (0.0000) no negative values will be displayed.
0T
Inp.1Set the DecimalPoint position
Calibrate the Zero point
Set the Display valueequal to the Cal. weight
Calibrate the Span
Set the Display Step Size
Enter theSetup menu
Set the Display Upper Limit
Set the Display Lower Limit
DAS72.1
Page 5 DAS72.1 Manual Issue1c
QUICK SET UP AND CALIBRATION USING THE LOAD CELL mV/V SENSITIVITY
Press the UP or DOWN key for more than 3 seconds to enter the Set-up MenuSET UP
0T
Inp.1 SET THE DISPLAY UPPER LIMIT. (MAXIMUM VALUE +99,999)Use the UP/DOWN & MOVE RIGHT keys to set the maximum display value required.
0T
Inp.1 SET THE DISPLAY LOWER LIMIT. (MINIMUM VALUE -9,999)Use the UP/DOWN & MOVE RIGHT keys to set the minimum display value required.
SET THE DISPLAY STEP SIZE. (1, 2, 5, 10, 20, 50, 100, 200, 500)Use the UP or DOWN key to set the required display step size.
0T
Inp.1
CALIBRATE THE ZERO POINT.(CONVENTIONAL WEIGHING SYSTEM)Display shows the actual input signal in mV/V. Press the Enter key to store the zero.
0T
Inp.1
0T
Inp.1 SET THE SPAN CALIBRATION VALUE.Use the UP/DOWN & MOVE RIGHT keys to set the display value equivalent to the calibration weight or the calculated mV/V signal derived from the load cell(s) test data.
CALIBRATE THE SPAN FROM THE mV/V LOAD CELL SENSITIVITIES
Press the Enter key to store this value.
Use the UP/DOWN & MOVE RIGHT keys to set the mV/V reading equivalent to the span calibration value set in section 2.1.
0T
Inp.1
SET THE DECIMAL POINT POSITION (0, 0.0, 0.00, 0.000, 0.0000)Use the UP or DOWN key to set the required decimal point position. Please note that with 4 decimal places set (0.0000) no negative values will be displayed.
0T
Inp.1Set the DecimalPoint position
Calibrate the Zero point
Set the Display valueequal to mV/V sensitivity
Set the mV/V equivalentto Span Calibration Value
Set the Display Step Size
Enter theSetup menu
Set the Display Upper Limit
Set the Display Lower Limit
DAS72.1
ENTERING THE SETUP MENU DAS72.1
Press the UP or DOWN key for more than 3 seconds to enter the Set-up MenuSET UP
SET UP AND CALIBRATE ZERO FUNCTION / SWITCH LOAD CELL EXCITATION TO 10VDC (TEST MODE)
SET UP AND CALIBRATE SPAN FUNCTION / DISPLAY INPUT SIGNAL IN mV/V - See Next Page
0T
Inp.1
0T
Inp.1
TTTInp.2
TTTInp.2
ZERO KEY DISABLED.The zero key will not operate in normal weighing mode
ZERO KEY ENABLED.(Limit ± 2% of Upper Display Limit)The zero key will operate in normal weighing mode
0T
Inp.1
0T
Inp.1
CALIBRATE OR ADJUST THE ZERO POINT.(CONVENTIONAL WEIGHING SYSTEM)Display shows the actual input signal in mV/V. Press the Enter key to store the zero.
0T
Inp.1
TTTInp.2
0T
Inp.1
CALIBRATE THE ZERO POINT FROM THE LOAD CELL mV/V READINGUse the UP/DOWN & MOVE RIGHT keys to set the mV/V reading at which the unit should read zero.
0T
Inp.1
TTTInp.2
0T
Inp.1
SET THE LOAD CELL SUPPLY VOLTAGE TO 10V DCThis sets the load cell excitation to 10 VDC to make load cell fault finding easier.
0T
Inp.1
TTTInp.2
0T
Inp.1
Page 6 DAS72.1 Manual Issue1c
SET UP AND CALIBRATE SPAN FUNCTION / DISPLAY INPUT SIGNAL IN mV/V
SET UP THE DISPLAY - See Next Page
0T
Inp.1
0T
Inp.1
TTTInp.2
0T
Inp.1 SET THE SPAN CALIBRATION VALUE.Use the UP/DOWN & MOVE RIGHT keys to set the display value equivalent to the calibration weight or the calculated mV/V signal derived from the load cell(s) test data.
TTTInp.2 CALIBRATE THE SPAN. (CONVENTIONAL WEIGHING SYSTEM)
Display shows the actual input signal in mV/V. Apply test weights equivalent to the calibration value set in section 2.1. Press the Enter key to store the new span value.
0T
Inp.1
0T
Inp.1
CALIBRATE THE SPAN FROM THE LOAD CELL mV/V READINGUse the UP/DOWN & MOVE RIGHT keys to set the mV/V reading at which the unit should read the value set in section 2.1.
0T
Inp.1
TTTInp.2
0T
Inp.1
DISPLAY THE INPUT SIGNAL IN mV/VThis function allows you to view the input signal in mV/V.
0T
Inp.1
TTTInp.2
0T
Inp.1
DAS72.1
Page 7 DAS72.1 Manual Issue1c
SET UP THE DISPLAY
FILTER SETTINGS & NO MOTION - See Next Page
0T
Inp.1
TTTInp.2
TTTInp.2
TTTInp.2
TTTInp.2
0T
Inp.1
0T
Inp.1SET THE DISPLAY UPPER LIMIT. (MAXIMUM VALUE +99,999)Use the UP/DOWN & MOVE RIGHT keys to set the maximum display value required.
SET THE DISPLAY LOWER LIMIT. (MINIMUM VALUE -9,999).Use the UP/DOWN & MOVE RIGHT keys to set the minimum display value required.
0T
Inp.1
0T
Inp.1
SET THE DISPLAY STEP SIZE. (1, 2, 5, 10, 20, 50, 100, 200, 500)Use the UP or DOWN key to set the required display step size.
0T
Inp.1
0T
Inp.1
SET THE DECIMAL POINT POSITION ON THE DISPLAY (0, 0.0, 0.00, 0.000, 0.0000)Use the UP or DOWN key to set the required decimal point position. Please note that with 4 decimal places set (0.0000) no negative values will be displayed.
0T
Inp.1
0T
Inp.1
DAS72.1
Page 8 DAS72.1 Manual Issue1c
FILTER SETTINGS & NO MOTION
ANALOGUE OUTPUT SETTINGS - See Next Page
0T
Inp.1
0T
Inp.1
0T
Inp.1
TTTInp.2 SET THE FILTER CUT OFF FREQUENCY IN Hz. (RANGE 0.3 - 33.3Hz)
Use the UP/DOWN & MOVE RIGHT keys to set the cut off frequency required.
SET THE NUMBER OF DIVISIONS CHANGE (JUMP) ABOVE WHICH THE FILTER (4.1) IS BYPASSED.Use the UP/DOWN & MOVE RIGHT keys to set the number of divisions change above which the filter (4.1) is bypassed. This allows the unit to respond quickly to large changes but remain stable at the end values.
0T
Inp.1
TTTInp.2
0T
Inp.1
SET THE ZERO MOTION LIMITUse the UP or DOWN key to set the required no motion limit for the zero. If the zero is changing by a number in excess of this limit the zero key is disabled.
0T
Inp.1
TTTInp.2
0T
Inp.1
SET THE TARE MOTION LIMITUse the UP or DOWN key to set the required no motion limit for the tare. If the tare is changing by a number in excess of this limit the tare key is disabled.
0T
Inp.1
TTTInp.2
0T
Inp.1
DAS72.1
Page 9 DAS72.1 Manual Issue1c
ANALOGUE OUTPUT (4-20mA) SETTINGS
RELAY 1 SETTINGS - See Next Page
0T
Inp.1
0T
Inp.1
0T
Inp.1
TTTInp.2 SET THE NUMBER OF DIVISIONS AT WHICH 4mA IS SENT
Use the UP/DOWN & MOVE RIGHT keys to set the number of divisions at which 4mA is sent.
SET THE NUMBER OF DIVISIONS AT WHICH 20mA IS SENT.Use the UP/DOWN & MOVE RIGHT keys to set the number of divisions at which 20mA is sent..
0T
Inp.1
TTTInp.2
0T
Inp.1
SET THE ANALOGUE OUTPUT BASE (gros, net, off)Use the UP or DOWN key to set the analogue output base : gros - the analogue output follows the Gross value: net - the analogue output follows the net value : off - the analogue output is switched off.
0T
Inp.1
TTTInp.2
0T
Inp.1
TEST MODE FOR THE CURRENT OUTPUT Use the UP or DOWN & MOVE RIGHT key to set a current value in mA, which will be sent down the analogue output, independent of the load applied to the weighting system.
0T
Inp.1
TTTInp.2
0T
Inp.1
DAS72.1
Page 10 DAS72.1 Manual Issue1c
RELAY 1 SETTINGS
RELAY 2 SETTINGS - See Next Page
0T
Inp.1
0T
Inp.1
0T
Inp.1
TTTInp.2 SET THE NUMBER OF DIVISIONS (SETPOINT) AT WHICH RELAY 1 OPERATES
Use the UP/DOWN & MOVE RIGHT keys to set the number of divisions at which Relay 1 operates (Setpoint).
SET THE HYSTERSIS VALUE ON SETPOINT 1.Use the UP/DOWN & MOVE RIGHT keys to set the hystersis value on Setpoint 1.
0T
Inp.1
TTTInp.2
0T
Inp.1
SET RELAY 1 MODE (BASE) ( groS, nEt,)Use the UP or DOWN key to set the mode of operation of Relay 1 (base): groS - Relay 1 operates when the Gross value reaches the setpoint : nEt - Relay 1 operates when the net value reaches the setpoint.
oFF, oFF - Relay 1 is disabled :
0T
Inp.1
TTTInp.2
0T
Inp.1
TEST MODE FOR RELAY 1 (Eng, dEEng)Use the UP or DOWN key to energize (Eng) or de-energize (dEEng) relay 1.
0T
Inp.1
TTTInp.2
0T
Inp.1
DAS72.1
Page 11 DAS72.1 Manual Issue1c
RELAY 2 SETTINGS
DATACOM SETTINGS - See Next Page
0T
Inp.1
0T
Inp.1
0T
Inp.1
TTTInp.2 SET THE NUMBER OF DIVISIONS (SETPOINT) AT WHICH RELAY 2 OPERATES
Use the UP/DOWN & MOVE RIGHT keys to set the number of divisions at which Relay 2 operates (Setpoint).
SET THE HYSTERSIS VALUE ON SETPOINT 2.Use the UP/DOWN & MOVE RIGHT keys to set the hystersis value on Setpoint 2.
0T
Inp.1
TTTInp.2
0T
Inp.1
0T
Inp.1
TTTInp.2
0T
Inp.1
0T
Inp.1
TTTInp.2
0T
Inp.1
DAS72.1
SET RELAY 2 MODE (BASE) ( groS, nEt)Use the UP or DOWN key to set the mode of operation of Relay 2 (base): groS - Relay 2 operates when the Gross value reaches the setpoint : nEt - Relay 2 operates when the net value reaches the setpoint.
oFF, oFF - Relay 2 is disabled :
Page 12 DAS72.1 Manual Issue1c
TEST MODE FOR RELAY 2 (Eng, dEEng)Use the UP or DOWN key to energize (Eng) or de-energize (dEEng) relay 2.
DATA COMMUNICATION SETTINGS
SET UP AND CALIBRATE ZERO FUNCTION / SET LOAD CELL EXCITATION TO 10V DC
0T
Inp.1
0T
Inp.1
0T
Inp.1
TTTInp.2 SET THE BAUD RATE (9600, 19200, 38400, 115200)
Use the UP or DOWN key to set the required baud rate.
SELECT EITHER RS422 OR RS485 INTERFACE.Use the UP or DOWN key to select either the RS422 or the RS485 interface.
0T
Inp.1
TTTInp.2
0T
Inp.1
SET THE DEVICE ADDRESS (0-255)Use the UP/DOWN & MOVE RIGHT key to set the device address (multi-drop) Set to 0 for single point to point applications.
0T
Inp.1
TTTInp.2
0T
Inp.1
SELECT AUTO TRANSMIT MODE (groS, nEt, oFF)Use the UP or DOWN key to set a the auto transmit mode.: oFF - the auto transmit is switched off.: groS - the unit continuously transmits the gross value : nEt - the unit continuously transmits the net value : All - the unit sends all data.(See Programmers Manual for details)
0T
Inp.1
TTTInp.2
0T
Inp.1
DAS72.1
Page 13 DAS72.1 Manual Issue1c
Display overload (Display value exceeds the upper limit set in Menu 3.1)
The Zero or Tare motion limit has been exceeded. Set Zero or Tare function disallowed. Review Zero and Tare motion limits set in menus 4.3 and 4.4
Display underload (Display value is more negative than the lower limit set in Menu 3.2 or you have set 4 digits after the decimal placeand you are trying to display a negative number)
Set final zero out of range. (You are trying to set a zero which is greater than ±2% of the Upper Display Limit menu 3.1)
Excessive sensitivity requested. (The input signal is being divided into too many divisions i.e the size of each division is less than 0.5uV)
The input signal is in excess of ± 2.6 mV/V
Faulty load cell connection (Open circuit / Short Circuit / Wire disconnected)
You are trying to enter a value which is not valid (Outside the acceptable parameter range)
The zero key is not enabled (See menu 1.1)
DAS72.1ERROR CODES
Page 14 DAS72.1 Manual Issue1c
If you need to return the DAS72.1 to the factory settings simply press and hold the recessed enable switch whilst powering up the unit. All parameters will then revert to the factory settings
ASCII protocol format:Baudrate 9600/19200/38400/115200
Data bits 8-bits
Stop bits 1-bit
Parity NONE
ASCII protocol commands:
Single shot commands
Command Response strings Operation
SZ<CR> OK<CR>/ERR<CR> Set a new Zero value
RZ<CR> OK<CR>/ERR<CR> Revert to original calibration Zero
OP <XXX><CR> OK<CR>/ERR<CR> Open connection to channel XXX
CL<CR> Close channel connection
IV<CR> V:XXXX<CR> Returns Software Version Number (XXXX)
ID<CR> D:DAS<CR> Returns Device Identity (DAS)
IS<CR> S:XXXYYY<CR> Returns Device Status (XXXYYY)
ST<CR> OK<CR>/ERR<CR> Set a new Tare value
RT<CR> OK<CR>/ERR<CR> Revert to Gross mode
GG<CR> G 00000<CR> Get the Gross value
GN<CR> N 00000<CR> Get the Net value
SG<CR> G 00000<CR> Send the Gross value continuously
SN<CR> N 00000<CR> Send the Net value continuously
IM<CR> IM:XXXX<CR> Input Mask - Disable push button functions
IN<CR> IN:XXXX<CR> Read Inputs Status
OM<CR> OM:XXXX<CR> Output Mask - Disable Setpoint outputs
IO<CR> IO:XXXX<CR> Rad / Modify Output Status
LI<CR> Lists all menu values
DAS72.1COMMUNICATION PROTOCOL AND COMMANDS
Page 15 DAS72.1 Manual Issue1c
CALIBRATION PROCEDURE USING WEIGHTS DAS72.1
It is assumed that the load cell system is connected to the DAS72.1 and the power
is on. The maximum and minimum display values, display increment size and
decimal point position should be defined prior to carrying out the calibration (See
Menu 3). For this example the display maximum is define as 2009, the display
minimum is -200, the display step size is 1 and there is no decimal point.
Remember that all parameters under sections 1.1 - 1.3, 2.1 - 2.3 and 3.1 - 3.4 can
only be accessed or changed after the Recessed Enable Switch has been pressed.
a) Go to Menu 1.2 and using the UP/DOWN and RIGHT keys set the display to
read 0000.Make sure that the weighing system is empty or at the point where
you want the display to read zero. Press the 0 [Enter] key. This defines the
actual zero calibration point.
b) Go to Menu 2.1 and using the UP/DOWN and RIGHT keys set the display to
read the value of the calibration weight(s) applied. For this example if the
calibration load applied is 2000Kg set the display to read 2000. Press the 0
[Enter] key. This defines the calibration weight.
Example:3 leg tank or silo fitted with 3 off 1000Kg 2mV/V load cellsDead load 500Kg, Live range 2000Kg in 1 Kg steps
c) Go to Menu 2.2. Apply the calibration weight(s) to the weighing system. Press the 0 [Enter] key. The display to show the actual input signal in
mV/V. Press the 0 [Enter] key. This defines the actual span calibration point. The display will show 2.2. Press the right arrow key twice and the
DAS will be back in weighing mode.
Calibration is now complete
Page 16 DAS72.1 Manual Issue1c
CALIBRATION PROCEDURE USING KNOWN LOAD CELL MV/V SENSITIVITY DAS72.1
MULTIPLE ACTIVE LOAD CELLS
It is assumed that the load cell system is connected to the DAS72.1 and the power
is on. The maximum and minimum display values, display increment size and
decimal point position should be defined prior to carrying out the calibration (See
Menu 3). For this example the display maximum is define as 2009, the display
minimum is -200, the display step size is 1 and there is no decimal point.
Remember that all parameters under sections 1.1 - 1.3, 2.1 - 2.3 and 3.1 - 3.4 can
only be accessed or changed after the Recessed Enable Switch has been pressed.
a) Go to Menu 1.2. Press the 0 [Enter] key. The display will read the input signal in
mV/V.
Press the 0 [Enter] key. This defines the actual
zero calibration point.
b) Go to Menu 2.1 and using the UP/DOWN and RIGHT keys set the display to
read the capacity of the load cell system or the weight value at which the
sensitivity is known. For this example the load cell capacity is 3 x 1000Kg =
3000Kg @ 2mV/V. Set the display to read 3000. Press the 0 [Enter] key. This
defines the theoretical calibration weight (equivalent to 2mV/V in this example).
Make sure that the weighing system is empty or at the point where you
want the display to read zero.
Example:3 leg tank or silo fitted with 3 off 1000Kg 2mV/V load cellsDead load 500Kg, Live range 2000Kg in 1 Kg steps
c) Go to Menu 2.3. the UP/DOWN and RIGHT keys set the display to read the mV/V sensitivity of the load cell
system you are using. For this example the load cell sensitivity or Output at Rated Load is 2.000mV/V. In multiple load cell installations (load
cells wired in parallel) the sensitivity is the average of all the load cells connected. Press the 0 [Enter] key. This defines the theoretical span
calibration point.
d) If required the zero can be re-calibrated without affecting the span. To do this make sure that the weighing system is empty or at the point
where you want the display to read zero. Goto Menu 1.2. Press the 0 [Enter] key. The display shows the actual input signal in mV/V.
Press the right arrow key twice and the DAS will be back in weighting mode.
Calibration is now complete
Press the 0 [Enter] key. Use
Press the
0 [Enter] key.
Page 17 DAS72.1 Manual Issue1c
CALIBRATION PROCEDURE USING KNOWN LOAD CELL MV/V SENSITIVITY DAS72.1
SINGLE ACTIVE LOAD CELL PLUS HINGE PIVOT
It is assumed that the load cell system is connected to the DAS72.1 and the power
is on. The maximum and minimum display values, display increment size and
decimal point position should be defined prior to carrying out the calibration (See
Menu 3). For this example the display maximum is define as 2009, the display
minimum is -200, the display step size is 1 and there is no decimal point.
Remember that all parameters under sections 1.1 - 1.3, 2.1 - 2.3 and 3.1 - 3.4 can
only be accessed or changed after the Recessed Enable Switch has been pressed.
a)
b) Go to Menu 2.1 and using the UP/DOWN and RIGHT keys set the display to
read the capacity of the load cell system or the weight value at which the
sensitivity is known. For this example the load cell capacity is 2000Kg @ 2mV/V.
But the hinge pivot on the opposite side of the tank carries half the load (if the
centre of gravity is in the middle of the tank). Therefore when there is 4000Kg in
Go to Menu 1.2. Press the 0 [Enter] key. The display will read the input signal in
mV/V. Make sure that the weighing system is empty or at the point where you
want the display to read zero. Press the 0 [Enter] key. This defines the actual
zero calibration point.
Example:A rectangular tank fitted with 1 off 2000Kg 2mV/V load cell central on the left hand side and a pivot (hinge) along the complete opposite face . Dead load 500Kg, Live range 2000Kg in 1 Kg steps
the tank equally split between the load cell and the hinge the output from the load cell will be 2 mV/V. The system is therefore 4000Kg
@2mV/V. Set the display to read 4000. Press the 0 [Enter] key. This defines the theoretical calibration weight (equivalent to 2mV/V in this
example).
c) Go to Menu 2.3 and using the UP/DOWN and RIGHT keys set the display to read the mV/V sensitivity of the load cell system you are using.
For this example the load cell sensitivity or Output at Rated Load is 2.000mV/V. In multiple load cell installations ( load cells wired in parallel)
the sensitivity is the average of all the load cells connected. Press the 0 [Enter] key. This defines the theoretical span calibration point.
d)
PLEASE NOTE THAT IF THE LOAD IS NOT EQUALLY SHARED BY THE LOAD CELL AND PIVOT THE CALIBRATION WILL BE INACCURATE.
If required the zero can be re-calibrated without affecting the span. To do this make sure that the weighing system is empty or at the point
where you want the display to read zero. Goto Menu 1.2. Press the 0 [Enter] key. The display shows the actual input signal in mV/V. Press the
0 [Enter] key. Press the right arrow key twice and the DAS will be back in weighting mode.
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