SKF Multilog On-Line System IMx-M, Руководство пользователя

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Protection
Protection Part Operation
2 - 58 SKF Multilog On-Line System IMx-M
User Manual
Disarm
There are three different types of disarm;

Channel disarm

Slot disarm

Rack disarm
Important - In order to engage disarm when relays are configured to trigger on
channels in more than one protection module or solely on channels of a PRM in a
different slot, it is strongly recommended always to use
rack disarm input to
disarm the entire rack at once.
The disarm status is stored in the backplane and will be recovered after a power cycle
or hot-swap procedure.
Channel Disarm

Channel disarm can be set through Local display selection keypad by selecting
CHANNEL ACTION then ARM/DISARM CH.
Local display selection keypad is located
on each condition monitoring module.

It can also be set through Modbus register 258 as described in Imported (Write
Single) Modbus Register .
The characteristics of channel disarm:

Latching cable fault is not triggered during channel disarm.

Latching cable fault issued before disarm is kept during channel disarm mode (user
must be sure to manually reset latching cable faults).

Alert relays go to state OK when associated channel(s) enter channel disarm mode.

Danger relays go to state OK when associated channel(s) enter channel disarm
mode.

Not OK relays go to state OK when associated channel(s) enter channel disarm
mode.

For the behavior of channel disarm relay, refer to the table
Behavior of channel status
relays
in Relays chapter.

For combined measurements, if the corresponding channel X or channel Y is in
channel disarm, then the combined measurement will be set to channel disarm.

Warning! Exercise extreme caution where N-out-of-N alarm logic is being used, as
any of those channels in disarm will mean that the condition will never be TRUE
(relay can never be triggered).