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5
5.7 Input / Output Modules
5.7.2.3 Parameterization of Energy Pulses
If you want to use the binary outputs for energy measurement, you have to calculate the smallest
possible input (kWh/pulse) first. Please use the following description:
1. Select the pulse length (e.g. 200 ms). Refer to the table in chapter 5.7.2.2 for the maximum
number of pulses/h: 14400
2. Calculation of the maximum load to be connected:
Single-phase circuit: Maximum load to be connected =
(Voltage measuring range Ph-N x Transformation ratio of the voltage transformer) x (Cur-
rent measuring range x Transformation ratio of the current transformer)
e.g.:
U
P
Three-phase or four-phase circuit: Maximum load to be connected = (Voltage measuring
range Ph-N x Transformation ratio of the voltage transformer) x (Current measuring range
x Transformation ratio of the current transformer) x 3
e.g.:
U
P
3. Calculation of the minimum energy increase per pulse
Depending on the pulse length and the maximum number of pulses/h the following calcula-
tion applies:
Singl-phase circuit:
P
/ 14400 puls/h = 331.2 W / 14400 puls/h =
max/W
0.023 Wh/puls = 0.000023 kWh/puls
Three-phase or four-phase circuit:
P
/ 14400 puls/h = 993.6 W / 14400 puls/h =
max/W
0.069 Wh/puls = 0.000069 kWh/puls
For the example, the smallest energy increase is as follows:
Singl-phase circuit: 0.000023 kWh/puls
Three-phase or four-phase circuit: 0.000069 kWh/puls
If you use a setting higher than these values the increase of energy will be registered cor-
rectly.
Note
The smallest possible input values only apply if the connected load is close to the threshold of
the measuring range of the device. If the connected load is smaller, the calculated values may
also be smaller.
Note
A transformation ratio >1 has to be used in the calculation described above and in the parame-
terization of the device.
94
= 276 V, T
= 1; I
Ph-N, max
U
= U
x I
= 331.2 W
max
Ph-N, max
max
= 276 V, T
= 1; I
Ph-N, max
U
= (U
x I
) x 3 = 993.6 W
max
Ph-N, max
max
= 1.2 A, T
= 1
max
I
= 1.2 A, T
= 1
max
I
Power Meter SICAM P 7KG7750/55, Manual
E50417-B1076-C340-A6, Edition 09.2013
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