Carlo Gavazzi WM3-96 - Manual (Page 37)

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Useful information
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Alarm parameters Example 4
The variables measured by the instrument are
correct if the inputs have been connected ac-
cording to the right polarities (see figure below).
Should the connection not be conforming to the
right polarities, measuring and retransmission errors
may occur, both due to the wrong direction of the current
flowing in the primary/secondary of the ammeter trans-
former being connected.
It is however possible to measure and retransmit currents/
powers according to the direction of their flow using correctly
the parameters "MIn U./Max U." and "Min IN/Max IN".
Example 1: it’s necessary to measure a consumed active
power up to 100kW considering that it may either be con-
sumed or generated by the system and retransmitted with a 4
to 20mA signal; the module to be used is AO1026 (2x from 0
to 20 mA) or AO1050 (1x from "MIn U./Max U." and "Min IN/
Max IN".0 to 20 mA) that is to be set as follows:
• VARIA.: W
Σ (
active system power)
• MIN U.: 20,0% corresponds to 4mA, the calculation formula
is: (100* min. output)/ fullscale output = 100*4mA/20mA=
20%
• MAX U.: 100,0% corresponds to 20mA, the calculation
formula is: (100* max. output)/ fullscale output= 100*20mA/
20mA=100%
• MIN IN: 0,0 K;the K,M and G multipliers are automatically
selected by the instrument depending on the selected VT
and CT value;
• MAX IN: 100,0 K; the K,M and G multipliers are automatically