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Restart inhibit – Rockwell Automation 937CU-DIFRQ_1 Universal Frequency Converter Installation Instructions User Manual

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Bul. 937

C Universal Frequency Converter Installation Instructions

Restart inhibit

Restart inhibit prevents temporary trip value violations or line faults (

Err LB, Err SC; Refer to Display

modes and error messages and Input) from not being noticed by operations personnel.

•If

Alarm freeze On has been selected, the new state is retained after an output is switched until one of the

following actions takes place:

–Device is restarted
–Signal on terminals 13/14

ESC key pressed.

Each of these actions will cause the switch output to be reset unless the trip value has been violated or the lead
fault is still present.

•If you have selected restart inhibit for an output with the switching direction

MIN, start-up override must

have been initiated when the device started up (See

Start-up override). The Universal Frequency

Converter always starts with a 0 measurement value. This will immediately trigger a MIN alarm.
Without start-up override, the output would then be blocked by restart inhibit.

Using the FDT parameterization software, pulse suppression can be selected as an alternative to start-up
override (See

Start-up override). If pulse suppression is selected in this manner, no restart inhibit is possible.

If problems occur with the restart inhibit, please use the software to check whether pulse suppression has
been selected.

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