AIC rating of service equipment

[cwain]

I am trying to determine the AIC rating of a panel and the only thing I see is 100k EHD, What does EHD stand for ? Does that mean the Breaker has 100k AIC rating?

 

[Dennis Alwon]

That would be my guess but I don't know what EHD stands for. It may be the breaker frame

Did a google and it looks like a cuter hammer "type"

 

[cwain]

ok thanks

 

[Eastham11]

And if this is only on the panel, the breaker may not have this high of a rating. Typically the panel box is rated at a standard 100k or 200k, but the installed main/branch breakers may be lower; the lower rating must be used.

 

[templdl]

I am trying to determine the AIC rating of a panel and the only thing I see is 100k EHD, What does EHD stand for ? Does that mean the Breaker has 100k AIC rating?

You appear to be asking a leading question often times in a way to get the answer that they want to hear.
If this is a service entrance there should be a the name of the manufacturer, the panel type and the nameplate/label on it which should include all of the ratings.

Often times the OP includes a smattering of info where we as respondents have to guess as to what you are getting at.

Your reference to a panel, you completely blew past who the panel manufacturer was, the type of panel and it’s nameplate with the ratings.
You mention EHD, you also stated 100K but completely failed to state who the manufacturer was, when there are KAIC ratings on the breaker there are also voltage ratings for each of them.
I'm going out on a limb and am going to ASSUME that the "EHD" being referred to in an Eaton, Cutler-Hammer, or Westinghouse breaker which are all in the same.
As such, this breaker is available in a 1,2, and 3p frame from 15 to 100AT. The 1p is rated for up to 277v, the 2 and 3p 480v. The KAIC ratings are 14 KAIC @ 277v, 18KAIC @240, and 14KAIC@480v.

Now, getting back to you OP "I am trying to determine the AIC rating of a panel and the only thing I see is 100k EHD, What does EHD stand for? Does that mean the Breaker has 100k AIC rating?"

Where does the 100K come in? When the the EHD breaker has a max of 18KAIC at 480v.

 

[cwain]

It is a 200 amp 3 PH Cutler Hammer panel . On the main Breaker in top right hand corner is 100k EHD 240v, 65k 480v ( I wanted to make sure this was the AIC because I did not know what EHD meant.)

At the bottom of panel on the cover on a sticker it says something like this. ( The AIC Rating of this panel is based upon the smallest AIC rating of any device installed in this panel. Except otherwise noted in the Series Rating Information.

I noticed that the branch circuit breakers were only 10K rated so this kind of worried me because the available fault current at this building location is 35k and the inspector made it clear we would have to install service equipment rated 35k or better. This building has only 2- 200 amp 3 ph service panels and no sub- panels. I assume these panels are series rated based on the info Im getting here. My question now is , what is the requirements of using series rated panels verses fully rated panels?

 

[cwain]

It is a 200 amp 3 PH Cutler Hammer panel . On the main Breaker in top right hand corner is 100k EHD 240v, 65k 480v ( I wanted to make sure this was the AIC because I did not know what EHD meant.)

At the bottom of panel on the cover on a sticker it says something like this. ( The AIC Rating of this panel is based upon the smallest AIC rating of any device installed in this panel. Except otherwise noted in the Series Rating Information.

I noticed that the branch circuit breakers were only 10K rated so this kind of worried me because the available fault current at this building location is 35k and the inspector made it clear we would have to install service equipment rated 35k or better. This building has only 2- 200 amp 3 ph service panels and no sub- panels. I assume these panels are series rated based on the info Im getting here. My question now is , what is the requirements of using series rated panels verses fully rated panels?

 

[kingpb]

You still have not mentioned what voltage you are using.

Would propose you contacting manufacturer to confirm but I beleive you will find the breaker is rated 100KA @ 240Vac, and 65kA at 480Vac.

 

[kwired]

It is a 200 amp 3 PH Cutler Hammer panel . On the main Breaker in top right hand corner is 100k EHD 240v, 65k 480v ( I wanted to make sure this was the AIC because I did not know what EHD meant.)

At the bottom of panel on the cover on a sticker it says something like this. ( The AIC Rating of this panel is based upon the smallest AIC rating of any device installed in this panel. Except otherwise noted in the Series Rating Information.

I noticed that the branch circuit breakers were only 10K rated so this kind of worried me because the available fault current at this building location is 35k and the inspector made it clear we would have to install service equipment rated 35k or better. This building has only 2- 200 amp 3 ph service panels and no sub- panels. I assume these panels are series rated based on the info Im getting here. My question now is , what is the requirements of using series rated panels verses fully rated panels?

If branch breakers are rated 10K then they better be listed in the series rating information otherwise the entire panel is only rated 10K.

You say fault current at the building is 35K. I don't know exactly what that means. If this is the service panel it probably means there is 35K available at the supply terminals, if it is a subpanel within the building the fault current may be lower than what is at the service because of impedance of feeders ahead of the panel. If it is fault current available at utility transformer, it will be lower at the service equipment, how much depends on size and length, type of service conductors. Every piece of equipment needs its own calculation to determine available fault current as it will be different at each one.

 

[Jraef]

If branch breakers are rated 10K then they better be listed in the series rating information otherwise the entire panel is only rated 10K.

If you're not familiar with this concept, this is what he means by "series rated".

Some (most) mfrs of panel boards and breakers will test specific combinations of breakers in series with one another and the series rating of the combination may be higher that the lowest individual component. The concept takes advantage of the "let through" current of the up stream devices. So to find out, the ONLY valid way is to contact the mfr., they will have a list of devices that are series rated. Generally though, if this was properly done at the outset, the panel should have had a sticker declaring it. If yours does not, and it appears that way from your description, it's a valid concern. But that doesn't mean for sure it is not, I believe you can still do it on your own, but you need to be prepared with the data from the manufacturer showing the series rating of ALL of the devices in that panel. If even one of them is not on the list, then it reverts to the rule on the sticker you already saw.

 

[templdl]

It is a 200 amp 3 PH Cutler Hammer panel . On the main Breaker in top right hand corner is 100k EHD 240v, 65k 480v ( I wanted to make sure this was the AIC because I did not know what EHD meant.)

At the bottom of panel on the cover on a sticker it says something like this. ( The AIC Rating of this panel is based upon the smallest AIC rating of any device installed in this panel. Except otherwise noted in the Series Rating Information.

I noticed that the branch circuit breakers were only 10K rated so this kind of worried me because the available fault current at this building location is 35k and the inspector made it clear we would have to install service equipment rated 35k or better. This building has only 2- 200 amp 3 ph service panels and no sub- panels. I assume these panels are series rated based on the info Im getting here. My question now is , what is the requirements of using series rated panels verses fully rated panels?

I'm a bit intregued as to where the 100k rating came from.
I have attached a copy of the technial specs for the EHD.
Unless there is more to the story then you have already told where is this leading to?

 

[Jraef]

I'm a bit intregued as to where the 100k rating came from.
I have attached a copy of the technial specs for the EHD.
Unless there is more to the story then you have already told where is this leading to?

I'd bet he transposed the letters from an EDH...