Fuses or Breakers

[MyCleveland]

What about the sccr at 5 KA. Is that an issue with residential stuff being at 10 KA?

It could be but doubtful.
Small wire is your friend, chokes the AFC down quickly.
Assume FULL 10k AFC at your panel.
Just 5' from your panel...
#10 CU > 4282 AFC
#8 CU > 4530 AFC
#6 CU > 4692 AFC

 

[Eddie702]

The units used to say fuse or hacr breaker.

Yes they did, unless they wanted fuses. Then it would say "fuse only" You don't see the call for fuses only on units very often.

 

[electrofelon]

Yes they did, unless they wanted fuses. Then it would say "fuse only" You don't see the call for fuses only on units very often.

I don't think I have seen one that's says "fuse only", usually it's just "fuse".

 

[Dennis Alwon]

I don't think I have seen one that's says "fuse only", usually it's just "fuse".

I remember reading here that it was more common in commercial units. But that was quite a while ago.

 

[Eddie702]

I have seen units marked "fuses only" but not often. But often enough to make me read the label LOL

Maybe it is a thing of the past. I remember a chiller I wired years ago that was marked fuses only. They had specified NEMA 4x stainless steel disconnects. I had already bought unfused disconnects because I had the correct breakers in the indoor panel. Had to return the chiller disconnect and buy a fusible one in its place.

I remember trying to drill the disconnects to use a KO punch and went through a few drill bits. Then someone told me when you drill stainless run the drill bit as slow as possible which helped a lot

 

[electrofelon]

I have seen units marked "fuses only" but not often. But often enough to make me read the label LOL

Maybe it is a thing of the past. I remember a chiller I wired years ago that was marked fuses only. They had specified NEMA 4x stainless steel disconnects. I had already bought unfused disconnects because I had the correct breakers in the indoor panel. Had to return the chiller disconnect and buy a fusible one in its place.

I remember trying to drill the disconnects to use a KO punch and went through a few drill bits. Then someone told me when you drill stainless run the drill bit as slow as possible which helped a lot

It should be "fuse only". Would have saved 10's of thousands of hours of discussion over the years and people doing it wrong......