PROGRAMMING EXAMPLES OF THE ANALOGUE OUTPUTS
Power retransmission by means of a 0-20mA analog output.
It’s necessary to measure a consumed power up to 100kW and retrans-
mit this value by means of a signal from 4 to 20 mA: the module to be
used is AO2050 (2x from 0 to 20mA), the instrument is to be programmed
as follows:
VARIABLE:
W
∑
(system active power).
MIN OUT:
20.0% means 4 mA the calculation to be carried out is the fol-
lowing: (100*minimum output) / fullscale output =100*4mA/ 20mA=20%.
MAX OUT:
100.0% means 20mA, the calculation to be carried out is:
(100*maximum output) / fullscale output = 100*20mA/20mA= 100.
MIN INPUT:
0,0k; the multiple k,M,G can be selected on the instrument
according to the chosen VT and CT values.
MAX INPUT:
100.0k; the k, M, G multiples can be selected on the instru-
ment according to the selected VT and CT values.
Retransmission of the POWER FACTOR (PF) by means of the
0-20mA analog output.
It’s necessary to retransmit the whole range of the admitted values for the
PF with a signal from 0 to 20mA. Particular attention must be paid to the
value of the PF variable which may vary from C0,001 and L0,000 (for each
phase): these values will be retransmitted and will then correspond to 0
and 20 mA. When the PF will have a value equal to 1, being in the mid-
dle between C0,001 and L0,000, the value of the output will correspond
to the middle of the scale, that is 10mA. As a consequence, the instru-
ment will have to be programmed 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 in order to avoid any unde-
sirable swifting of the repeated outputs.
PROGRAMMING WM30-96
CARLO GAVAZZI
A u t o m a t i o n C o m p o n e n t s
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