One-Channel Or Two-Channel Connection To An Fso Module; General; Implementing The Reset Of The Safety Function; Indications Of The Safety Function - ABB ACS880-01 Application Manual

20 Implementing a motor thermal protection circuit

One-channel or two-channel connection to an FSO module

￭

General

This section describes two implementations of the ATEX-compliant motor thermal protection
circuit with an FSO module:
• The circuit uses the ATEX-certified Safe disconnection function (option +Q971) of the
drive.
• The FSO module (FSO-12 or FSO-21) is connected to the drive STO terminals.
• The protection relay is connected to the FSO module either with:
• a two-channel (redundant) connection, or
• a one-channel (non-redundant) connection. In this case, one output contact of the
protection relay is used for monitoring the status of the relay.
Note: The STO function of the drive must always have a redundant connection. See
Connection diagram (two-channel connection) (page 21)
connection) (page 22).
If you plan to use the one-channel connection in the protection relay, make sure that you
can reach the necessary safety integrity level (SIL). According to standard EN 50495, SIL1
is sufficient for the protection of category 2 and 3 equipment.
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Implementing the reset of the safety function

A manual reset is mandatory in the motor thermal protection function, if it is required for
ensuring the compliance of the system with Ex/ATEX regulations. After the motor thermal
protection function activates, the motor must not restart before a manual reset command is
given. You can implement a manual reset in the ATEX-compliant protection relay
(recommended). Use the reset button of the relay, or connect an external reset button to
the relay.
In this example, you can also configure a manual reset either in:
• the drive with the motor overtemperature (one-channel connection only) or STO indication
parameters. See section
• the FSO module by connecting a reset circuit to the FSO module. See section
module (page 27).
￭

Indications of the safety function

In this example, an indication of the safety function can come from several sources:
• the motor overtemperature indication in the drive (one-channel connection only)
• the STO indication in the drive
• the STO or SS1 indication in the FSO module.
If you want to avoid parallel indications in overtemperature situations, you can set one or
several of the indication parameters value to No indication (or None) or Event:
• the motor overtemperature indication with drive parameters 31.01...31.02 or
35.11...35.12
• the STO indication in the drive with drive parameter 31.22 STO indication run/stop
• the STO or SS1 indication in the FSO module with FSO parameter FSOGEN.61 STO
indication ext request.
See section Reset method and status indications (page 25)
Reset method and status indications (page
or Connection diagram (one-channel
25).
or FSO module (page
FSO
27).