108 Connect Devices
WAGO-I/O-SYSTEM 750 XTR
750-495/040-00x 3-Phase Power Measurement Module 690 V
Manual
Version 1.2.0
7.6.1.1.2 Voltage Measurement on 2 Line Conductors
For voltage measurement, set the topology to “4-Wire Wye, 2-Phase” (“4-W/2-P”)
in WAGO-I/O-
Check
.
This topology is available with firmware versions 05 and above and WAGO-
I/O-
Check
versions IO-3.18.1 (CS0609) and above.
This measurement circuit is used in all grounded 3-phase networks with a neutral
conductor.
The measurement circuit basically corresponds to the “Grounded 3-Phase
Network with Neutral Conductor for Power Measurement and Voltage
Measurement on 3 Line Conductors for U
LN
≤
400 V
RMS
” connection schematic,
but without the voltage measurement of phase L2.
Voltage measurement is performed directly. The voltages U
L1
and U
L3
are
measured. The I/O module calculates the voltage U
L2
internally from the
measurement results.
The current measurement is performed via current transformers (CTs) or
Rogowski Coils.
The current transformer ratio must be taken into account for the correct
calculation of all values in the process image.
The nominal input voltage is:
- U
LN
= 200 V
RMS
if a voltage ≤
120 V
RMS
is parameterized for the “Secondary
Voltage” setting
- U
LN
= 400 V
RMS
if a voltage > 120 V
RMS
is parameterized for the “Secondary
Voltage” setting
Parameter 47 is used for the setting.