Phase loss protection for refrigerated shipping (Reefers) 1

[bacon4life]

Do refrigerated shipping containers usually have built in phase loss protection? We are considering whether to use fuses or a recloser/sectionalizer on the medium voltage side for a 1500 kVA padmount transformer feeding a contain terminal area. If the reefers don't have loss of phase protection, would a shunt trip on the 480V panel make more sense than a 3 phase medium voltage switching device?

An older thread discussed phase loss protection for building loads, but not mobile applications. This is for a USA port, but the reefers are global.

http://www.eng-tips.com/viewthread.cfm?qid=180860

 

[waross]

Many containers that I have worked on have a phase reversal relay. Many new refrigeration compressors will operate in either direction when they are put into service. There is a valve plate that is dragged into position by the rotor in the compressor so that either direction of rotation will work properly. When the compressor has been running for a few years the plate may be stuck in position and not move to the opposite position or only move part way if the motor is reversed. The rule of thumb is to keep track of the connections on a hermetic or semi hermetic compressor and never reverse the rotation of the motor.
I have seen a lot of reefers that have phase rotation relays and two contactors so that the compressor always runs the same direction regardless of the phase rotation of the feed.
I doubt that these units would start with a phase missing but I am not sure what would happen if a phase was lost when the motor was running.

Bill
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"Why not the best?"
Jimmy Carter