Analog Output Configuration Examples - Allen-Bradley PowerMonitor 500 User Manual

Analog Output Configuration
Examples
These examples apply to units with catalog numbers 1420-V1A and 1420-V2A.
Example 1: Power value retransmission with a 0...20 mA analog output.
This example describes how to retransmit measured power up to
100 kW with a 4...20 mA signal. Program the unit as follows:
• VARIABLE: W
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• MIN OUT: 20.0% means 4 mA. The calculation that is used is the
following:
(100*minimum output) / full scale output =100*4 mA/ 20 mA=20%
• MAX OUT: 100.0% means 20 mA. The calculation is the following:
(100*maximum output)/full scale output = 100*20 mA/20 mA= 100
• MIN INPUT: 0.0 k; the multiplier k, M, G can be selected on the unit
according to the chosen VT and CT values
• MAX INPUT: 100.0 k; the k, M, G multipliers can be selected on the unit
according to the selected VT and CT values
Example 2: Retransmission of the power factor (PF) value with the
0...20 mA analog output.
In this example, the unit is configured to retransmit the whole range of the
allowed values for the PF with a signal from 0...20 mA. The value of the PF
variable can vary between C0.001 and L0.000 (for each phase); these values,
when retransmitted, correspond to 0 mA and 20 mA. When the PF value is equal
to 1, the analog output value corresponds to the middle of the scale,
which is 10 mA. Program the instrument as follows:
• VARIABLE: PF L1 (or L2 or L3 or PF
• MIN OUT: 0.0%
• MAX OUT: 100.0%
• MIN INPUT: C0.001 (the C symbol shows a CAPACITIVE value)
• MAX INPUT: L0.001 (the L symbol shows an INDUCTIVE value).
L0.001 has been chosen as minimum value to be set to avoid undesirable
rapid changes of the outputs
Rockwell Automation Publication 1420-UM001E-EN-P - March 2016
(system real power)
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Unit Configuration Chapter 3
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