Mcb's tripping when appliance is plugged in

[stratplus]

Hello all,
The appliance is a display fridge. Three phase on its own circuit.
As soon as it is turned on at the isolator the display flashes and mcb's immediately trips.
This appliance has only just developed this fault.
All connections look ok at the appliance and three phase plug.
Could a component fault cause this like a fan? Although this was disconnected both line and neutral and it still tripped.

 

[GLENNSPARK]

well....your appliance is the culprit....so disconnect and test it....be sure to verify theres nothing in the appliance that could be damaged/give fake readings though first wont you....

 

[Darkwood]

If its run consistently on this circuit before without issue and has only just recently developed this problem then the fridge has a fault or you have low insulation on the circuit itself which faults under load. IR the circuit if ok then get refrigerator engineer out but could be anything from fridge light fault to compressor..... the list is extensive as regards to the components and control wiring of fridge all of which may be the issue. Unless your competent in fridge diagnostic and repair id get it repaired by others if you do attempt to look into it be careful you don't IR any electronics on the fridge like the display or in some cases the control board.

 

[stratplus]

Thank you both for the quick replies. Didn't have my insulation tester with me today to check. I'll be checking the basics in next week.
Would have though an electrical fault rather the fridge circuit as isn't there only a compressor with any electricity. There's nothing electrical in evap or condenser side.

 

[Darkwood]

You gave us limited info.... 3ph fridge so assume commercial or industrial ...is it walk in or more a superstore set up?, does it have display lighting?..... your house fridge may be basic compressor and door light but larger fridges can have a lot more to them.

 

[guinnessgixer]

I used to repair domestic fridges, we used to get a lot of trouble with the starter on the side of the compressor, when they were tripping out, but under test they would give excellent IR reading.

 

[farmerian]

Most Likly the fridge compressor or fan if its a shop floor display fridge

 

[MDJ]

All connections look ok at the appliance .

Did you use a magnifying glass?

 

[stratplus]

It's a cold display fridge on commercial premises. No lights, just the usual fan, compressor, condenser and evaporator.