CVHF Trips

[grendil]

I have 3 CVHF Chillers. I'm having intermitten Main Breaker Trips. Motor Megs fine, Contacts great. It does have a tracer connected to siemens apogee.
Chiller runs great. It could be at 60% and trip or 80%. It's only on one chiller. Monitered voltage for several weeks looks ok. has anyone heard of oil heater tripping a main? Any ideas. Pondered change out the Breaker too much $$ to throw a try.

[19 D Guy]

Don't know if this has anything to do with it or not. I am finishing up a teardown on a CVHF 910, it had several trips at main breaker. The last time I went in had shut down on a diagnostic, found contacts burnt. Unwired motor and megged put and motor megged fine. Two weeks later customer approved replacement of contacts, we went over to replace. Machine came online and tripped main breaker. Megged motor out again and guess what, bad motor. Don't know if this is a trend but I have never had anything like this happen before. Good luck

[fixerup]

I have seen breakers trip prematurely when the starter cabinet gets hot.Does the starter panel have fans and are they working? Just a thought .

[grendil]

We added fans this winter.

[drivewizard]

Have the breaker tested.

[jimbob73]

Does the breaker have a shunt trip coil?

[txhvac]

An oil heater will not trip a main breaker. If your megger results read fine, and your starter contacts are clean, is all electrical tight? Is there any corrosion any where? Are the terminals @ the peckerhead clean & snug? Is the starter unit mounted or remote? Meg the line and load wires DISABLING them from both the main & peckerhead. There could possibly be a short in the conduit somewhere. You said you have 3 chillers, I am assuming that only one of them is having the problem. Like one of the other fellas said you could have breaker issues. Its going to be a process of elimination. Hope this helps.

[cateyes]

if your current draw is normal, have your breaker tested

[jayguy]

Have the breaker tested.

yup. we had a breaker trip several years ago on a 1280 ton machine...it did have a hole blown through the windings so...ok. rebuilt unit. recommended having the breaker checked out since it did trip. they said they did. maybe, maybe not. ran chiller after overhaul...ran great. shut the chiller down. unit was in post lube cycle...1/4 hp motor at 115 VAC. tripped the circuit breaker. we RE-recommended that they have the breaker checked again. another unit started tripping the breaker...bad shunt. replaced breaker...all ok.

good luck.

[clgman]

In my opinion, it depends on the design and rating of the breaker, what type of fault and how long it exists that may trip the breaker. Any load, no matter how insignificant may trip a breaker if the magnetic inrush exceeds the rating of the device. I would get a new megger or rent one and test all of the conductors, devices, and the motor. Contact the Breaker manufacture and get their input on how many faults the device can suffer before testing or replacement is recommended. Maybe call on a large electric motor rebuider in the area to see if they might recommend an outfit that can monitor the circuit with equipment that will recognize the fault. Good luck.

[grendil]

Does the breaker have a shunt trip coil?

It has a Digi trip, which was replaced at the time of the 1st trip.

[heatingman]

have some pictures taken with a thermal camera of your switch gear, inside the starter cabinet, and the compressor terminals, during a loaded condition. this will show if poor connections are at fault.