Supply Connection; Main Contactor - ABB ACSM1 Hardware Manual

Supply connection

Use a fixed connection to the AC power line.
WARNING! As the leakage current of the device typically exceeds 3.5 mA, a fixed
installation/connection is required according to IEC 61800-5-1. Additionally, one of
the following requirements must be fulfilled:
a) protective earthing conductor cross-section of at least 10 mm
b) automatic disconnection of the supply in case of discontinuity of the protective
earthing conductor, or
c) a second protective earthing conductor of the same cross-sectional area as the
original protective earthing conductor to the second terminal.

Main contactor

Install a main contactor on the grid side of the ACSM1-204 regen supply module and
WFU-xx regen filter module. The main contactor must be controlled so that it is
disconnected always when the regen supply module is not in use, it is stopped or it is
faulty. The regen supply module may sustain damage if not disconnected in such a
situation.
The contactor can be controlled from the I/O or RO in the JCU of the regen supply
module. In this case, external powering for the JCU control unit is needed and
should be done by supplying 24V to connector X1 in the JCU of the ACSM1-204.
A contactor is needed for the following reasons:
• If the regen filter module is connected to the grid while the regen supply unit is not
modulating/active, there is a risk that the filter responds to disturbance
frequencies in a distorted grid and starts resonating, which may cause permanent
damage to the regen supply module, filter and equipment connected to the DC
bus. If the regen supply module is stopped, faulty or otherwise inactive, it cannot
influence the resonance of the filter.
• The regen supply module and regen filter module cannot prevent power flow from
the grid to the DC bus and further to the ACSM1-04 drives. Even if the modulation
of the ACSM1-204 regen supply module is stopped, the anti-parallel diodes of
the inverter bridge in ACSM1-204 enable power flow to the DC bus and to the
motor inverters. In other words, merely stopping the regen supply module does
not stop the system.
• The regen supply module is not protected against excessive current drawn from
the DC bus. If the motoring power (power demanded from the DC bus) exceeds
the supplying capability of the regen supply module, it trips. If the current demand
remains or increases, the regen supply module is damaged.
2
Cu or 16 mm
Planning the electrical installation
39
2
Al,