48 Planning the electrical installation
Protecting the contacts of relay outputs
Inductive loads (relays, contactors, motors) cause voltage transients when switched
off.
Equip inductive loads with noise attenuating circuits (varistors, RC filters [AC] or
diodes [DC]) in order to minimize the EMC emission at switch-off. If not suppressed,
the disturbances may connect capacitively or inductively to other conductors in the
control cable and form a risk of malfunction in other parts of the system.
Install the protective component as close to the inductive load as possible. Do not
install protective components at the I/O terminal block.
Drive
relay
output
Drive
relay
output
Drive
relay
output
Varistor
RC filter
Diode
230 V AC
24 V DC
230 V AC
Summary of Contents for ACS355 series
Page 1: ...ABB machinery drives User s manual ACS355 drives ...
Page 4: ......
Page 16: ...16 ...
Page 32: ...32 Operation principle and hardware description ...
Page 58: ...58 Electrical installation ...
Page 74: ...74 Start up control with I O and ID run ...
Page 106: ...106 Control panels ...
Page 120: ...120 Application macros ...
Page 178: ...178 Program features ...
Page 338: ...338 Fieldbus control with embedded fieldbus ...
Page 368: ...368 Fault tracing ...
Page 404: ...404 Dimension drawings ...
Page 410: ...410 Appendix Resistor braking ...
Page 434: ...434 Appendix Permanent magnet synchronous motors PMSMs ...