WAGO-I/O-SYSTEM 750 XTR
Connect Devices 125
750-495/040-00x 3-Phase Power Measurement Module 690 V
Manual
Version 1.2.0
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.
For measurement of the neutral conductor, ensure that the neutral conductor
current does not exceed the maximum current of the I/O module. If applicable,
use a current transformer with a higher transformation ratio.
7.6.1.9 Measurement of Multiple Ungrounded Single-Phase Networks with
Different Neutral Conductors
The “4-Wire Wye” (“4-W”) topology is available in WAGO-I/O-
Check
for voltage
measurement.
This topology is fixed in firmware versions 04 and below and selectable in
WAGO-I/O-
Check
in firmware versions 05 and above.
The voltage transformer ratio can be parameterized in firmware versions 05 and
above and WAGO-I/O-
Check
versions IO-3.18.1 (CS0609) and above.
Up to 3 ungrounded single-phase networks with different neutral conductors can
be connected to the I/O module.
Voltage measurement is performed via voltage transformers (VTs). Voltages u
L1
,
u
L2
and u
L3
are measured. The I/O module calculates voltages U
L1
, U
L2
and U
L3
internally from the measurement results.
The current measurement is performed via current transformers (CTs) or
Rogowski Coils.
The measured values of unconnected voltage and current measurement inputs
have no significance. The measured values for the line-to-line voltages that the
I/O module outputs have no significance either.
The voltage transformer ratio and current transformer ratio must be taken into
account for the correct calculation of all values in the process image.
Always use voltage transformers with basic insulation and ground the
module-side N connection
When connecting multiple ungrounded single-phase networks with different
neutral conductors, always use voltage transformers with at least basic insulation
and ground the module-side N connection.
Otherwise, touch-proof protection from the system may no longer be given in the
event of a fault. This can cause electric shock or burns.