20A CB tripped?

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anbm

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We have bring 20A circuit, protected by 20A/1P breaker to sterilizer with information as indicated below from equipment cutsheet:

Dedicated line 120V, NEMA 5-20R outlet, 20A circuit, wire gaurd sufficient to maintain 16A continuous load with a 40A momentary current.

They have told us when equipment started, the CB tripped. Do you know what percentage can 120V - 20A/1PH CB can be overloaded? I think momentary current is not a factor in this case and not sure what CB is tripped while manufacturer cutsheet indicates we only need to provide only
20A circuit as stated above, even they did not state about CB size requirement but we can go by outlet and circuit size.
 
most manufacturers have a 20 amp breaker designed for higher than normal inrush loads. That might solve your problem.
(example SquareD QOB120HM)
 
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Unless the equipment is truely defective you can probably find a 20A breaker with a delayed trip curve for overloads in this range. Does the manufacturer state how long the inrush lasts ? If they have a toll free number I would give them a call to see if they recommend a specific 20A breaker they know will work.

Your fast Augie47 !
 
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anbm said:
They have told us when equipment started, the CB tripped. Do you know what percentage can 120V - 20A/1PH CB can be overloaded? I think momentary current is not a factor in this case and not sure what CB is tripped while manufacturer cutsheet indicates we only need to provide only 20A circuit as stated above, even they did not state about CB size requirement but we can go by outlet and circuit size.
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Along with the inrush current, mentioned by augie47, we need to know the manufacturer and catalog number of the breaker.

Most 'panelboard breakers' can handle 2X rated current for many minutes and 5X current for several seconds.
 
jim dungar said:
Along with the inrush current, mentioned by augie47, we need to know the manufacturer and catalog number of the breaker.

Most 'panelboard breakers' can handle 2X rated current for many minutes and 5X current for several seconds.
Click to expand...

I have seen breakers run at 120% indefinitely (not intentionally). :)
 
petersonra said:
I have seen breakers run at 120% indefinitely (not intentionally). :)
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Actually 120% indefinitely would not surprise me at all. At this point in the breaker and fuse performance curves the air temperature around the protective device has a lot of influence over its operating time. I do not know of any breaker or fuse curves that even show the 100% operating point.
 
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