ABB ACS480-04-09A8-1, Hardware Manual, Page: 66 / 240

wye). For other systems, refer to Compatibility of EMC filter and ground-to-phase varistor
with the grounding system (page 66) .
Note: If you disconnect the EMC filter, the electromagnetic compatibility of the drive
decreases.
WARNING!
Do not install a drive with the internal EMC filter connected to a grounding system
that the EMC filter is not compatible with (for example, an IT system). The supply
network becomes connected to ground potential through the internal EMC filter
capacitors, which can cause danger or damage to the drive.
￭
Ground-to-phase varistor
The drive has a ground-to-phase varistor circuit as standard. You can install a drive that
has the varistor circuit connected to a symmetrically grounded TN-S system
(center-grounded wye). For other systems, refer to
Compatibility of EMC filter and
ground-to-phase varistor with the grounding system (page 66) . In some product variants,
the varistor circuit is disconnected at the factory.
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.
￭
Compatibility of EMC filter and ground-to-phase varistor with the
grounding system
WARNING!
If you do not obey these instructions, injury to personnel or damage to the drive
can occur.
A metal EMC screw is used to connect the internal EMC filter, and a metal VAR screw
is used to connect the ground-to-phase varistor. The screws are installed at the factory.
The material of the screws (plastic or metal) depends on the product variant. Before
66 Electrical installation – IEC