Eaton EMR-4000, Инструкция по установке, эксплуатации и обслуживанию

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EMR-4000 IM02602009E
Thermal Block
Besides the previously mentioned start monitoring and controlling means, the motor can be blocked if the thermal
capacity used exceeds the alarm level. It is the User’s choice to turn on or off this feature and set an appropriate alarm
level in the thermal model module.
Blocked Condition
Note that the protective device has two types of blocking outputs: individual block and a general block. The individual
blocking functions are as follows:
•
Number of cold starts block;
•
Time between starts block;
•
Starts per hour block;
•
Anti-Backspin block;
•
Thermal block (from thermal model); and
•
External starting block
When any of Anti-Backspin, thermal, and external blocks are on, the general blocked flag will be set. The TBS and
SPH can turn on the general blocked flag only if the motor is not in a cold start sequence; NOCS block can not cause
the general blocked flag to be set.
Forced Starting
It is recommended that the User wires the general blocked output to the motor trip circuit for preventing the motor from
starting under these blocked conditions. If the User chooses not to do this for their applications, a Forced Starting flag
will be set when the motor is started with the blocked conditions. This flag can only be reset manually though
PowerPort-E or from the front panel.
Trips and Trip Bypass
If any of the motor protective functions operate while the motor starts or runs, the protective device can open its trip
contact if so configured. It may also open its trip contact after a stop is recognized if any jogging function time limit is
blocking the next start. In either case, the protective device expects that the contactor has opened in response and that
no current flows.
If the protective device senses noticeable current for more than about a second whenever it is tripped, it sets a Trip
Bypass flag. This means that the relay blocking of the contactor has been circumvented by the User to start the motor.
If the current fails to stop when the protective device trips a running motor, it may be because of a User trip bypass or
because of a stuck contactor.
Consider the possibility of backup protection for a contactor opening failure. Configure one of the output relays to pick
up for a trip bypass. Connect the contact to trip an upstream breaker. This protects the motor from damage in case of
a stuck contactor (at the cost of interrupting other loads connected to the same breaker).
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