25 amp breakers

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I installed several of them in Square D, GE and Siemans panels. They were for specific equipment (Marconi Rectifiers) that called out for 2P-25A breakers. That was the only time I have used them.
 
Pretty common here. Got a 4500W water heater?

4500?240=18.75

18.75?1.25=23.4

That needs a 2 pole 25.
 
chris kennedy said:
Pretty common here. Got a 4500W water heater?

4500?240=18.75

18.75?1.25=23.4

That needs a 2 pole 25.

I don't believe you must use a 25 amp breaker.They use to require a 25 amp breaker here but you can use 150% for non motor operated appliance.

art. 422.11(E) Single Non?motor-Operated Appliance. If the branch circuit supplies a single non?motor-operated appliance, the rating of overcurrent protection shall comply with the following:
(1) Not exceed that marked on the appliance.
(2) Not exceed 20 amperes if the overcurrent protection rating is not marked and the appliance is rated 13.3 amperes or less; or
(3) Not exceed 150 percent of the appliance rated current if the overcurrent protection rating is not marked and the appliance is rated over 13.3 amperes. Where 150 percent of the appliance rating does not correspond to a standard overcurrent device ampere rating, the next higher standard rating shall be permitted.
 
brother said:
After reading about some 'no so common' breakers being used. I ran across some 25 amp breakers. How often do you use 25 amp breakers??? Ive seen 15 amp, 20, and 30 amp. didnt even know they made 25 amp breakers. ;)

Once in a while I run into an A/C unit or heat pump with a 25 amp max breaker.
 
480sparky said:
A lot of AC compressers I'm wiring in houses these days state MAX BREAKER SIZE 25 AMPS on the nameplate.

When you see "MAX SIZE 25 AMPS'' what is the "Minimum size XX amps" ? Have you had trouble with breakers tripping using the Minimum breaker size? I don't run into to many heat pumps but I do about 20 A/C units a year. I usually go with the max circuit size but on occasion I will use a less then max size breaker if it is a standard size and it is minimum or higher.(like a 30amp breaker, on a 35amp max rating.)
 
Dennis Alwon said:
I don't believe you must use a 25 amp breaker.They use to require a 25 amp breaker here but you can use 150% for non motor operated appliance.

I don't understand that statement if the math shows their above 13.3 amps and per your statement of #2.

You saying pay attention to the cutoff point ! Not that he missed his, LOL !

art. 422.11(E) Single Non–motor-Operated Appliance. If the branch circuit supplies a single non–motor-operated appliance, the rating of overcurrent protection shall comply with the following:
(1) Not exceed that marked on the appliance.
(2) Not exceed 20 amperes if the overcurrent protection rating is not marked and the appliance is rated 13.3 amperes or less; or
(3) Not exceed 150 percent of the appliance rated current if the overcurrent protection rating is not marked and the appliance is rated over 13.3 amperes. Where 150 percent of the appliance rating does not correspond to a standard overcurrent device ampere rating, the next higher standard rating shall be permitted.
 
cadpoint said:
I don't understand that statement if the math shows their above 13.3 amps and per your statement of #2.

You saying pay attention to the cutoff point ! Not that he missed his, LOL !

art. 422.11(E) Single Non?motor-Operated Appliance. If the branch circuit supplies a single non?motor-operated appliance, the rating of overcurrent protection shall comply with the following:
(1) Not exceed that marked on the appliance.
(2) Not exceed 20 amperes if the overcurrent protection rating is not marked and the appliance is rated 13.3 amperes or less; or
(3) Not exceed 150 percent of the appliance rated current if the overcurrent protection rating is not marked and the appliance is rated over 13.3 amperes. Where 150 percent of the appliance rating does not correspond to a standard overcurrent device ampere rating, the next higher standard rating shall be permitted.

I am referring to Chris K. statement on a 4500 watt element. I thought Chris was saying that you had to use a 25 amp. breaker based on 4500/240 multiplied by 1.25. He got 23 or so amps. Statement 3 says you can use 150% of the rated current for OCP and then use the next higher OCP if you fall in between standard size breakers.

I am not saying that you can't use a 25 amp breaker just that a 30 amp breaker would also be code compliant on a 4500 watt element
 
76nemo said:
Are you saying 20Ampere's won't tolerate the inrush of the unit/s???

I believe he is saying that the unit states 25 amp max. Most ec , I know, use the max. for the ocp to make sure there is no issue. I had a situation where I used a 30 instead of a 35 and the heating guy said the reason the a/c was tripping the breaker was because I didn't use the max. Had to go back and change it and I bet you will guess that changing the breaker didn't solve his problem. :grin:
 
Dennis Alwon said:
I believe he is saying that the unit states 25 amp max. Most ec , I know, use the max. for the ocp to make sure there is no issue. I had a situation where I used a 30 instead of a 35 and the heating guy said the reason the a/c was tripping the breaker was because I didn't use the max. Had to go back and change it and I bet you will guess that changing the breaker didn't solve his problem. :grin:


No,.... I am not a betting man. From your post, it doesn't sound like it did,.....am I correct????
 
Dennis Alwon said:
I am referring to Chris K. statement on a 4500 watt element. I thought Chris was saying that you had to use a 25 amp. breaker based on 4500/240 multiplied by 1.25. He got 23 or so amps. Statement 3 says you can use 150% of the rated current for OCP and then use the next higher OCP if you fall in between standard size breakers.

I am not saying that you can't use a 25 amp breaker just that a 30 amp breaker would also be code compliant on a 4500 watt element

I got it, I do understand that point & your statement of #3.

Its one of those quirks in the code that people remember, be it only a phrase and not correctly remember all the article as it should apply.

Thanks Dennis! And yes it was a refresher for me...
 
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