Coastalguy1
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- Virginia Beach, VA
I have a 26amp 120v lighting load which I want to control with a single pole switch. What size contactor do I supply and what breaker size?
thanks
thanks
26/.8 = 32.5A, so you need a circuit rated 35A minimum and a 35 or 40A breaker, so thereby a contactor rated to that circuit size.
Yes, but keep in mind that the contactor has to be protected by the upstream device. If he ends up using a 40A breaker and the contactor is only rated 30A, technically it's a problem for that contactor.I agree with the 35 amp conductor and breaker - unless this for some reason is not a continuous load - lighting generally is though.
I don't think the contactor needs rated 35 amps as long as it is not rated less than the load it is connected to. Keep in mind the contactor likely has a resistive load rating as well as an inductive load rating.
Or two circuits & two single pole switches and no contactor.or maybe two 20amp circuits thru a 2p contactor ???
I have a 26amp 120v lighting load which I want to control with a single pole switch. What size contactor do I supply and what breaker size?
thanks
What kind of lighting fixtures are we talking. If its more than a 20 amp circuit it has to be heavy duty lampholders, article 210.23(B)
Yes, but keep in mind that the contactor has to be protected by the upstream device. If he ends up using a 40A breaker and the contactor is only rated 30A, technically it's a problem for that contactor.
I suspect he is using a double pole contactor
No code reference other than the "suitable for use" rule, but I was just shooting from the hip. Here are the specs for the Sq. D 8903 contactors.Do you have a code reference in mind for that, in general switching devices are only required to be rated for the load they are controlling.
15 amp light switch on a 20 amp circuit etc.
No code reference other than the "suitable for use" rule, but I was just shooting from the hip. Here are the specs for the Sq. D 8903 contactors.
http://static.schneider-electric.us/docs/Motor Control/Lighting Contactors/8903CT9701.pdf
There's a chart on page 12, lower left, showing the maximum CB size for each rating of contactor. Turns out on that specific one, a 30A contactor can be protected by a 40A breaker. But not a 50A, there is a limit.
This is probably not totally true but I thought fuses had a faster response time than breakers???? Not sure why that would matter.Interesting that if I use fuses I am not limited.
Do you have a code reference in mind for that, in general switching devices are only required to be rated for the load they are controlling.
15 amp light switch on a 20 amp circuit etc.
Interesting that if I use fuses I am not limited.
I have a 26amp 120v lighting load which I want to control with a single pole switch. What size contactor do I supply and what breaker size?
thanks
Your question is a little confusing. Putting a 17.5A load on a 15A breaker would not be a good idea but I don't think that is what you are asking.I have a similar situation. We have a photocell of 2100W, which means 17.5A. Previously somebody put 20A breaker on this circuit, is it ok? Or do we really need a breaker which is less than 17.5A?