Analog Output
Manual EZIII
Operator/Installer
Fort Atkinson, Wisconsin USA
Panningen, The Netherlands
www.digi-star.com
D3708-US Rev D April 03, 2007
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Analog Output
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Operators Manual
ANALOG OUTPUT OPTION
The Analog Output Option provides an analog signal that is
proportional to the scale weight. The option is normally configured as
4-20mA with 0mA providing an error indication. 4- 20mA or 0 -5V
operation without error indication is optional. This option can be
added to any EZIII series indicator. The signal will be supplied through
J904 or J905 connector. Contact 1 = Signal, contact 8 = ground.
Setup
After setting up your EZ indicator for proper operation, four more
parameters are required for the analog output feature to function
properly (“ZEROUT”, “LOW WT”, “HIGHWT”, “ANALOG”).
CAUTION: Changing scale setup parameters (“ZEROUT” “LOW
WT”, “HIGHWT”,“lb-kg”, “ANALOG” etc.) will
change the analog output signal.
Zero balances the scale:
Before setting the analog parameters make sure the scale has
been zero balanced. This should be done when the scale
is empty by pressing and holding the zero key.
Zero Output “zerout”:
Normally “zerout” is set while the load cells are connected and the
scale is empty. This matches the minimum analog output
signal with no weight on the scale.
Low Weight “LOW WT”,
Low weight is the weight where the analog output is 4mA or 0V.
High Weight HIghWT”:
High weight is the weight where the analog output is 20mA or 5V.
D3708-US Rev D 3
Analog Output
Analog Mode “Analog”:
Analog mode chooses between the available output modes:
0-20mA with error indication (Default), 4-20mA, or 0-5V.
This setting must match the hardware jumper settings.
Examples
Example 1: Scale with 10000 kg capacity, Analog Output set to output
4mA at 0 kg and 20 mA at 10000 kg.
With the scale empty, perform a Zero/Balance for the scale display.
With the scale empty, set “zerout” so that the Analog Output zero is
the same as the display zero.
Set “low wt” to 0.
Set “HIGHWT” to 10000.
Example 2: Scale with 20000 kg capacity, Analog Output set to output
4mA at 5000 kg and 20ma at 16000 kg.
With the scale empty, perform a Zero/Balance for the scale display.
With the scale empty, set “zerout” so that the Analog Output zero is
the same as the display zero.
Set “low wt” to 5000.
Set “HIGHWT” to 16000.
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Operators Manual
How to set ZEROUT, LOW WT and HIGHWT
NOTE: Zero Output “zerout” must be set while the load cells are
connected and the scale is empty.
EZ2400(V):
1. Enter the long form setup by pressing and holding the Net-Gross
and then the On key. Hold both keys for 3 seconds.
2. The display will show: “PRESS SELECT OR GROSS FOR MENU
1-2-3-4-CALIB.-EXIT”
3. Press Select twice to go to menu 2.
4. Press several times the On key until the display shows
“zerout” followed by a value.
5. With the scale empty press the Zero key. The display will show
“zero” followed by 0.
6. Press On to confirm and advance to the next parameter.
7. Press On a few more times until the display shows Low Weight
“low wt”.
8. Enter the weight where the analog output signal should be 4mA or
0V. (Use the Select key to increase the flashing digit and the
Function key to select which digit is flashing)
9. Press On to confirm and advance to High Weight “highwt”.
10. Enter the weight where the analog output signal should be 20mA
or 5V. (Use the Select key to increase the flashing digit and the
Function key to select which digit is flashing)
11. Press On to confirm.
12. Exit the long form setup by pressing and holding the Tare key and
pressing the On key.
D3708-US Rev D 5
Analog Output
EZ3400(V) and EZ3600(V)
1. Enter code 219 on the numeric keypad then press Select.
2. The display will show “zerout” followed by a value.
3. With the scale empty press the Zero key.
4. The display will show “zero” and will return to its standard
weighing mode .
5. Enter code 241 on the numeric keypad then press Select. The
display will show “low wt” (low weight) followed by a value.
6. Use the numeric keypad to enter the weight where the analog
output signal should be 4mA or 0V.
7. Press On to confirm.
8. Enter code 242 on the numeric keypad then press Select. The
display will show “highwt” (high weight) followed by a value.
9. Use the numeric keypad to enter the weight where the analog
output signal should be 20 mA or 5V.
10. Press On to confirm.
Analog Output Signal
The Analog Output is updated 10 times a second and reflects the
“Analog Output Gross Weight” value which is derived using
“ZEROUT”, “LOW WT”, “HIGHWT” and “ANALOG” values. The
analog output will not necessarily follow the value displayed on the
indicator.
The “Analog Output Gross Weight” is not affected when the operator
performs a normal “Zero/Balance” of the display.
The “Analog Output Gross Weight” will always be gross and does not
change when the operator selects the Net or Load/Unload weight to be
displayed.
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Operators Manual
Calculating the Output Value
If the “Analog Output Gross Weight” is between “LOW WT” and
“HIGHWT”, the following calculation determines the Analog Output
Signal:
4mA + (16mA*(Analog Output Gross Weight – “Low Wt”)
(“HIGHWT” – “Low Wt”)
The minimum analog output value is 4mA or 0V.
If the “Analog Output Gross Weight” is less than “Low Wt”, the
Analog Output Signal will be 4mA or 0V.
The maximum analog output value is 20mA or 5V.
If the “Analog Output Gross Weight” is greater than “HighWt”, the
Analog Output Signal will be 20mA or 5V.
Special Circumstances
1. The analog output will hold its present level when operator enters
the menus to change the scale’s setup parameters.
2. The analog output will hold its present level during indicator
temperature calibration process (which can take up to 3 seconds).
Temperature calibration normally occurs every 20 minutes, but
occurs more often during the first 20 minutes of operation.
3. When D.A.N. 243 = “0-20mA” 4-20mA output signal with 0mA in
an error situation.
When D.A.N. 243=" 4-20mA" 4-20mA output signal without error
signal.
When D.A.N. 243="0- 5V" 0-5V output signal without error
signal.
4. An error condition exists if “zerout” has not been set.
5. An error condition exists if “low wt” is larger than the “High Wt”.
6. An error condition exists if the scale has an analog error
(“AD ERR”).
D3708-US Rev D 7
Analog Output
Specifications
Operating Temp. Range: -30 to +40 degree C
Output Signal:
0-20mA (Default)
4-20mA (optional) or 0 to 5V (optional)
0-20mA or 4-20mA Output Load Resistance: < 350 ohm
Resolution: 16 bits, 1LSB = 0.0015% of full scale range where 1 LSB
=244 nA or 7.5 mV
Nonlinearity: < +/- 0.012%
Gain plus Offset Error: +/- 0.15% max.
Temperature Drift: 50 ppm/degree C, 0.35% max.
Update rate: 10 times per second
Calibration
Calibration is an iterative process alternating between the “MIN” and
“MAX” because offset adjustments affect the gain and gain
adjustments affect the offset.
Enter the Analog Output Test mode.
Select the “MIN” mode and adjust the Offset potentiometer (R1) on
the Analog Output PCB assembly to get 0.0000 mA(0.0000V).
Select the “MAX” mode and adjust the Gain potentiometer (R3) to get
20.000mA(5.0000V).
Repeat steps 1 and 2 until adjustments are not needed.
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