ABB ACS880-01 Series, Application Manual, Page: 15 / 46

Implementing a motor thermal
protection circuit
Contents of this chapter
This chapter contains instructions on implementing an ATEX-compliant motor thermal
protection circuit using the ATEX-certified Safe disconnection function (Q971) of
the drive.
Overview
You can implement the motor thermal protection circuit with or without an FSO safety
functions module.
The FSO safety functions module (FSO-12 or FSO-21) is an optional device used with
ACS880 drives to implement safety functions. When an FSO module is installed, it reserves
the standard STO connection of the drive. With the safety function shown in this manual,
the FSO module activates the drive STO function (opens the STO circuit) immediately (STO)
or after a deceleration ramp (SS1). You can configure several different safety functions in
the FSO module at the same time. The wiring and parameter settings in this manual show
how to configure the ATEX-certified Safe disconnection function as a safety function in the
FSO module. For more information on the FSO module, see the FSO module user's manuals.
Note: You cannot connect the temperature sensor directly to the drive or FSO module. You
must use an ATEX-compliant protection relay in between.
Without an FSO module: The opening contacts of the protection relay(s) open the STO
circuit of the drive (see sections
Two-channel connection to drive STO terminals (page 16)
and One-channel connection to drive STO terminals (page 18) ). The STO stops the motor
(if running) and prevents the motor start.
With an FSO module: The opening contacts of the protection relay(s) activate the STO or
Safe stop 1 (SS1) function of the FSO module. The FSO module opens the STO circuit of
the drive (see section
One-channel or two-channel connection to an FSO module (page 20) ).
3
Implementing a motor thermal protection circuit 15