ABB ACH580-31 - Ground-To-Phase Varistor; When to Disconnect EMC Filter or Ground-To-Phase Varistor: TN-S, IT, Corner-Grounded Delta and Midpoint-Grounded Delta Systems and TT Systems

to disconnect the EMC filter. See section When to disconnect EMC filter or
ground-to-phase varistor: TN-S, IT, corner-grounded delta and midpoint-grounded
delta systems and TT systems (page 94).
WARNING!
Do not install the drive with the EMC filter connected to a system that the
filter is not suitable for. This can cause danger, or damage the drive.
Note: When the integrated EMC filter is disconnected, the drive EMC compatibility
is considerably reduced. See section Motor connection data (page 200).
￭
Ground-to-phase varistor
A standard drive with the ground-to-phase varistor connected can be installed to
a symmetrically grounded TN-S system. If you install the drive to another system,
you may need to disconnect the varistor. See section When to disconnect EMC
filter or ground-to-phase varistor: TN-S, IT, corner-grounded delta and
midpoint-grounded delta systems and TT systems (page 94).
WARNING!
Do not install the drive with the ground-to-phase varistor connected to a
system that the varistor is not suitable for. If you do, the varistor circuit can
be damaged.
￭
When to disconnect EMC filter or ground-to-phase varistor: TN-S, IT,
corner-grounded delta and midpoint-grounded delta systems and TT
systems
Requirements for disconnecting EMC filter and varistor and additional requirements
for different electrical power systems are given below.
Symmetrically grounded TN systems (TN-S systems, ie, center-grounded wye)
Do not remove EMC or VAR screws.
PE
L2
L3
L1
N
94 Electrical installation – IEC