compressor breaker keeps tripping

[Joel R Martinez]

There should be a normally open solenoid valve that dumps pressure from the air/oil reservoir to allow unloaded starting. They usually have some kind of muffler on the discharge. Those mufflers have been known to plug up. The valve could also be stuck closed.

 

[Joel R Martinez]

I am attaching pics of the exhaust and the solenoids .is this what you are referring that could be plug or solenoid stuck in the close position?

 

[retirede]

I am attaching pics of the exhaust and the solenoids .is this what you are referring that could be plug or solenoid stuck in the close position?

I don’t see any picts, but an easy check is to manually actuate the pressure relief valve that’s installed on the air/oil reservoir. If you relieve any pressure when the unit is not running, you have a problem.

 

[drcampbell]

There should be a normally open solenoid valve that dumps pressure from the air/oil reservoir to allow unloaded starting. They usually have some kind of muffler on the discharge. Those mufflers have been known to plug up. The valve could also be stuck closed.

It's not necessarily a solenoid valve. The unloading function is often incorporated into the pressure switch, and sometimes into a check valve.

Wherever it is, it's one of the first places to look when a compressor fails to start and often doesn't require more than cleaning out the crud & corrosion.

 

[retirede]

It's not necessarily a solenoid valve. The unloading function is often incorporated into the pressure switch, and sometimes into a check valve.

That’s true for a reciprocating compressor, but this one is a rotary screw. I’ve never seen an electric motor driven one of them that didn’t use a solenoid valve.

 

[jmartinez1959]

I am going to try to explain what is recently happening. The 1st compressor didn't pass the megger test, so another 40HP compressor was purchase. It ran good for about two days. Then the new compressor tripped, and it also tripped the old compressor 125A breakers that was on but not running. The Ingersoll Rand service man says that I need a time delay circuit breaker but doesn't give me a catalog number.
Can it be that this surge protection breaker or a thermal magnetic breaker is not, correct? It has a HEB2B100, and I was told this breaker has a 15 sec inrush window.
Question: does the AIC rating of 65KA@ 480V need to be higher?

 

[petersonra]

I am going to try to explain what is recently happening. The 1st compressor didn't pass the megger test, so another 40HP compressor was purchase. It ran good for about two days. Then the new compressor tripped, and it also tripped the old compressor 125A breakers that was on but not running. The Ingersoll Rand service man says that I need a time delay circuit breaker but doesn't give me a catalog number.
Can it be that this surge protection breaker or a thermal magnetic breaker is not, correct? It has a HEB2B100, and I was told this breaker has a 15 sec inrush window.
Question: does the AIC rating of 65KA@ 480V need to be higher?

HEB2 would make it a 2 pole breaker. but the OP says HEB3.

The AIC rating has to be higher than the available short circuit current. There is no way for anyone here to know what that is, but it is a good bet that you are OK with 65kAIC.

i don't understand why they bought a new compressor just because the motor failed the megger test.

 

[kwired]

Most won’t run backward. They’ll build up a lot of pressure against the closed inlet (almost instantly, just a revolution or two) and stall the motor.

He he, was hooking up a vacuum pump one time piping wasn't installed yet but there was a filter assembly installed on the inlet to the pump so it doesn't take in any debris (was for holding down work piece on a CNC router machine in a cabinet shop). Bumped motor to check rotation, got a big bang that scared the poop out of me. It was running wrong and the cover on the filter assembly couldn't take the reverse pressure bent the latches and popped off, and it never even got to full speed.

 

[kwired]

I am going to try to explain what is recently happening. The 1st compressor didn't pass the megger test, so another 40HP compressor was purchase. It ran good for about two days. Then the new compressor tripped, and it also tripped the old compressor 125A breakers that was on but not running. The Ingersoll Rand service man says that I need a time delay circuit breaker but doesn't give me a catalog number.
Can it be that this surge protection breaker or a thermal magnetic breaker is not, correct? It has a HEB2B100, and I was told this breaker has a 15 sec inrush window.
Question: does the AIC rating of 65KA@ 480V need to be higher?

Does your breaker have a magnetic trip adjustment? It might be set too low, many are at lowest setting from factory and is possible nobody changed it.

The 65KA rating has to do with how high the available fault current is, which is dependent on source size, impedance, and what resistance of conductors may be between the source and the device location, all those factors have an effect. Chances are the 65k is more than you need unless it is located at the service gear and the source is really close and is a somewhat large source. Length of service and or feeder conductors will lessen how high a rating is needed pretty quickly. As long as maximum available fault current is below 65kA this basically means the device shouldn't self destruct under a fault condition, but doesn't mean much at all when it comes to response time once trip level current is encountered.