7.6.1.6.2 Voltage Measurement On 2 Line Conductors - WAGO 750-495/040-00 Series Manual

WAGO-I/O-SYSTEM 750 XTR
750-495/040-00x 3-Phase Power Measurement Module 690 V

7.6.1.6.2 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 ungrounded 3-phase networks with a
neutral conductor.
The measurement circuit basically corresponds to the "Ungrounded 3-Phase
Network with Neutral Conductor for Power Measurement and Voltage
Measurement on 3 Line Conductors for U
connection schematic, but without the voltage measurement of phase L2. This
circuit is used for measuring power in ungrounded 3-phase networks with a
neutral conductor with only 2 voltage transformers.
Voltage measurement is performed via voltage transformers (VTs). Voltages u
and u are measured. From the measurement results, the I/O module first
L3
calculates voltage u
The current measurement is performed via current transformers (CTs) or
Rogowski Coils.
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
In ungrounded 3-phase networks with a neutral conductor, 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.
The nominal input voltage is:
- u = 200 V
LN
Voltage" setting
- u = 400 V
LN
Voltage" setting
Parameter 47 is used for the setting.
and then voltages U
L2
if a voltage ≤ 120 V
RMS
if a voltage > 120 V
RMS
Connect Devices 119
≤ 400 V and u
LN RMS
, U and U
L1 L2 L3.
is parameterized for the "Secondary
RMS
is parameterized for the "Secondary
RMS
≤ 400 V "
LN RMS
L1
Manual
Version 1.2.0