156 Connect Devices
WAGO-I/O-SYSTEM 750 XTR
750-495/040-00x 3-Phase Power Measurement Module 690 V
Manual
Version 1.2.0
Pos: 101 /Serie 750 (WAGO-I/O-SYST EM)/Anschließ en/Anschl ussbeispiel e/Analog eingänge/Leistungsmessung 750- 0495, 750- 0495/040-00x - 3-Leiter-
Anschluss an Y/Δ
-Netzen @ 33\mod_1542372882845_21.docx @ 508602 @ 2345545455345545455 @ 1
7.7
Power Measurement with 3-Wire Connection on
Y/Δ
Networks
Take additional protective measures for voltages on the N connection that
are dangerous if touched
Voltages up to the nominal input voltage of the I/O module (U
LN
/U
LL
) can be
measured directly if it is ensured that no voltage to ground that is dangerous if
touched can exist on the N connection of the I/O module during normal
operation. If this is not ensured, additional protective measures must be taken
(e.g., use of voltage transformers with basic insulation).
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.
For voltages above the nominal input voltage, use voltage transformers
It is essential to use voltage transformers (VTs) to measure voltages above the
nominal input voltage of the I/O module (U
LN
/U
LL
). The voltage transformer ratio
must be selected in such a way that the secondary voltages of the transformers
do not exceed the nominal input voltage of the I/O module.
Furthermore, the N connection on the module side must be grounded.
For line voltages U
LN
> 400 V
RMS
, use of voltage transformers with reinforced
insulation is required.
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.
Always use current transformers
For measuring current, it is essential to use current transformers.
For line voltages U
LN
≤ 400
V
RMS
, current transformers with basic insulation are
required. For line voltages U
LN
> 400 V
RMS
, current transformers with reinforced
insulation are required.
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. Furthermore, current
measurement without a current transformer can lead to a short circuit in the
power network and destruction of the I/O module.