Not enough amps

arron1987 said:

I have a 240v compressor in my garage. Its on a 40a breaker. The compressor needs 30 amps minimum to start. Sometimes it starts no bother, other times it trips the electric. Is there anything i can put in the line to boost the amps for start up. Thanks Arron

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Some breakers panels, normally the higher end panels allow allow you to install a slow trip breaker, sometimes that takes care of these problems.

The compressor really should be installed on the proper size breaker per the manufacturer. What gage wire is it running on? What kind of panel do you have?

Is there anything else connected to the circuit the compressor is on?
Jamie

=jamiedolan;260998]Some breakers panels, normally

the higher end panels allow allow you to install a slow trip breaker, sometimes that takes care of these problems.

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a slow trip breaker? are you speaking of adjustable trip breakers like Sq D I-Line?

Is there anything else connected to the circuit the compressor is on?

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ditto

If this is a single recep (240 volt, most likely is but...) you can use larger breakers, SOMETIMES. Tell us what the motor lists as amps and does it have internal thermal protection.

does the compressor provide a max or min circuit rating?

nap said:

=jamiedolan;260998]Some breakers panels, normally a slow trip breaker? are you speaking of adjustable trip breakers like Sq D I-Line?

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HI
I worded that poorly, I mean the breakers that have a different trip curve, Do they call them High magnetic trip? I didn't realize there was a breaker with an adjustable trip curve for 120/240 1P panels.


Jamie

nap said:

=jamiedolan;260998]Some breakers panels, normally a slow trip breaker? are you speaking of adjustable trip breakers like Sq D I-Line?

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I think Jamie is talking about "high magnetic" breakers made just for this purpose.

Also, I'm pretty sure we are dealing with either an Aussie, or a Brit, so I have no advice to offer, myself.

InPhase277 said:

I think Jamie is talking about "high magnetic" breakers made just for this purpose.

Also, I'm pretty sure we are dealing with either an Aussie, or a Brit, so I have no advice to offer, myself.

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glad you said that. I somehow missed the second post by the OP.

Arron, if you are outside the US, there may be somebody here that has some info for you but most of us are US so our rules are not going to be applicable to you.




got any info on these "high magnetic" breakers. Never heard of them or never heard them using that term.

nap said:

got any info on these "high magnetic" breakers. Never heard of them or never heard them using that term.

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Here is one page on Square D about some of them.

http://www.squared.com/us/products/circuit_breakers.nsf/unid/1E49571E7E13ED8585256D73005AEADF/$file/lacbFrameset.htm

Jamie

To the OP, A moderator on this site:

http://forum.doityourself.com/electrical-c-d-c-9/

by the name of french277V is familiar with European electrical systems. I saw him online earlier today, so you might want to make a post over there.

Jamie

nap said:

got any info on these "high magnetic" breakers. Never heard of them or never heard them using that term.

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The circuit breaker industry calls them "High Magnetic Withstand Circuit Breakers". Most of the ones I've ever came across were large frame breakers 125 A and up. I've seen them used for selective coordination purposes, such that a branch circuit short doesn't trip a main and kill a whole panel board.

arron1987 said:

Sometimes it starts no bother, other times it trips the electric.

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Besides customizing the breaker to this load you can put up to 1/2 ohm resistance in the line to limit the startup surge.