HCET thermal protector cutoff main function

Motor thermal protector 

Definite time : when the load overcurrent and the continuous overcurrent time reaches the set   time, the overload protector will trip automatically and reset automatically after 5 minutes.  The adjustment range of overcurrent time is 0.2~30S, the repeatability error of overcurrent time is ± 5 [%], and the setting error of overcurrent time is ± 10 [%].

Inverse time  : when the load is overcurrent and the duration reaches the time specified by the ratio of the load current to the current setting value in a curve of level 1 to 4 selected by the tripping level, the overload protector will automatically trip and reset after 5 minutes. 

Short circuit protection

When the ratio of the load current to the current setting value exceeds a certain value, it can be regarded as a short circuit. The overload protector trips within 0.5S. This value is called the instantaneous multiple. The adjustment range  is:

Winding motor: 2~4.5 times.

Squirrel cage motor: 2-9 times.

Other electromechanical equipment: refer to the above two options.

After the overload protector is tripped, the nixie tube displays "SHORT", and the instantaneous multiple indicator lights up.

Phase loss protection

When the current of any phase in three phases is less than one third of the minimum current setting value and the duration reaches a certain time value, the overload protector will automatically trip, which is the phase loss time. When tripping, the nixie tube displays "PHASE".

Phase unbalance protection

When the three-phase current unbalance reaches 50 [%] and the duration reaches a certain time value, the overload protector will automatically trip, which is the phase unbalance time.

When tripping, the nixie tube displays the current value of the maximum phase.

Phase dislocation protection.

The phase sequence of three-phase power supply is opposite to the original phase sequence, and the overload protector automatically trips within 0.2 seconds. When tripping, the digital tube displays the phase error sign "PR".