Ground-To-Phase Varistor - ABB ACS580-01 Hardware Manual

76 Electrical installation
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Ground-to-phase varistor

The ground-to-phase varistor is not suitable for use on an IT (ungrounded) system.
Disconnect the ground-to-phase varistor before connecting the drive to the supply
network. Check the table below.
WARNING! Do not install the drive with the ground-to-phase varistor
connected on an IT system (an ungrounded power system or a high-
resistance-grounded [over 30 ohms] power system), otherwise the varistor circuit can
be damaged.
Check from the table below if you have to disconnect the EMC filter (EMC) or ground-
to-phase varistor (VAR). For instructions on how to do this, see sections
R0...R3 on page 77
Frame EMC
sizes filter
EMC
screws
R0...R3 1 × EMC
-
R5...R9 2 × EMC
-
1
Drive
or Frames R4...R9
Ground- Symmetrically
to-phase grounded TN
varistor systems (TN-S
systems)
VAR
screws
- Do not disconnect
1 × VAR Do not disconnect Do not disconnect
- Do not disconnect
1 × VAR Do not disconnect Do not disconnect
2
L1
L2
L3
N
PE
on page 78.
Corner grounded
TN systems
1
Disconnect
Disconnect
L1
L2
L3
PE
Drive
Frames
IT systems
2
(ungrounded or
high-resistance
grounded [>30
ohms])
Disconnect
Disconnect
Disconnect
Disconnect
3
Drive
3
L1
L2
L3