4-4-4-6 AL SER Ampacity Rating For Sub Panel

[Spudland_Dave]

Finally decided on a location for my sub-sub panel...was going to use the 4ga THHN I had gotten free, but in pricing out the necessary conduit, I'm finding that it might be cheaper & easier to just get some 4-4-4-6 SER Aluminum and use that instead.
Looking at some various ampacity tables, I "THINK" the 4-4-4-6 is good for 65A? which would be fine for me, a 60A breaker is what I planned to use no matter what wire I go with (AL or the CU THHN I had)

 

[Speedy Petey]

It is good for 55A, depending on your code cycle, which is good for a 60A breaker.

 

[Spudland_Dave]

It is good for 55A, depending on your code cycle, which is good for a 60A breaker.

If its only good to 55A, why is it legal/safe to put it on a 60A breaker? No code here...so safety/doing it right is my only concern.

 

[Aceman]

If its only good to 55A, why is it legal/safe to put it on a 60A breaker? No code here...so safety/doing it right is my only concern.

You're allowed to round up to the next breaker size assuming the calculated load isn't over the wire ampacity.

 

[Spudland_Dave]

You're allowed to round up to the next breaker size assuming the calculated load isn't over the wire ampacity.

Calculated load...tricky one. Of course its going to be feeding my "power hungry" shop end...2x 50A welder outlets, 30A Compressor Outlets, the chances of pulling decent amount right there is possible...I'm only one guy, but a nice Plasma is on my shopping list...right there is the Compressor and some decent load on the welder outlet...plus lighting..

Might just look into Flex Conduit to use the 4ga Copper THHN I have on hand.. Without hijacking my own thread...when they list conduit fill charts, most i've seen show 1" Conduit as having a fill capacity of 4, 4ga conductors...which is fine, thats all I need. But how tight to pull will it be here in the real world?

Seems like conduit 1" and smaller is CHEAP...1.25"+ they start having you grab your ankles.

 

[bronc3buster842001]

2'' pvc conduit at Lowes here is like 5 bucks for a 10ft stick... Thats cheap

 

[hh76]

Calculated load...tricky one. Of course its going to be feeding my "power hungry" shop end...2x 50A welder outlets, 30A Compressor Outlets, the chances of pulling decent amount right there is possible...I'm only one guy, but a nice Plasma is on my shopping list...right there is the Compressor and some decent load on the welder outlet...plus lighting..

Might just look into Flex Conduit to use the 4ga Copper THHN I have on hand.. Without hijacking my own thread...when they list conduit fill charts, most i've seen show 1" Conduit as having a fill capacity of 4, 4ga conductors...which is fine, thats all I need. But how tight to pull will it be here in the real world?

Seems like conduit 1" and smaller is CHEAP...1.25"+ they start having you grab your ankles.

#4 through 1" will be pretty tight, but it's not that bad. Biggest key is making the run as straight as possible, no flex, and as few couplings/fittings as possible. When pulling wire, the guy pushing is far more valuable than the guy pulling.

If you do have to use flex, keep in unsecured until wire is pulled, that way you can shake it a bit while pushing the wire through.

As far as the 55a capacity on a 60a breaker, don't worry about it. You'll never be pulling 60a continuously. All the amperage ratings are based on heat build up, and unless the circuit is maxed out for quite a bit of time, it won't have time to overheat.

 

[Speedy Petey]

Calculated load...tricky one. Of course its going to be feeding my "power hungry" shop end...2x 50A welder outlets, 30A Compressor Outlets, the chances of pulling decent amount right there is possible...I'm only one guy, but a nice Plasma is on my shopping list...right there is the Compressor and some decent load on the welder outlet...plus lighting..

Outlets don't pull anything at all. It's what's plugged into them and running that does.
Are you going to use three compressors at the same time? Or two welders? (That I'd like to see actually )

IMO if you are going to have a stick or bigger mig welder, or a bigger plasma, you are already pushing it with only a 60A feeder.

 

[Spudland_Dave]

#4 through 1" will be pretty tight, but it's not that bad. Biggest key is making the run as straight as possible, no flex, and as few couplings/fittings as possible. When pulling wire, the guy pushing is far more valuable than the guy pulling.

If you do have to use flex, keep in unsecured until wire is pulled, that way you can shake it a bit while pushing the wire through.

I dont "Have" to use flex...I just figured, by the time I bought all the EMT, Fittings & Elbow's cost wise Im not ahead and I've got a PITA to install...sure the Flex doesnt look as elegant when installed, but once I sheath my attic room upstairs, nobody will ever see it.

Outlets don't pull anything at all. It's what's plugged into them and running that does.
Are you going to use three compressors at the same time? Or two welders? (That I'd like to see actually )

IMO if you are going to have a stick or bigger mig welder, or a bigger plasma, you are already pushing it with only a 60A feeder.

LOL, you got a point (and I'd like to see one guy use all those at once too)...I do have a stick already (Maxstar 150), of course I cant say I own any other welders at this time, but I would like a Millermatic 212 at some point and a Thermal Dynamics Cutmaster 52. The only 2 things I can see running at once would be the Plasma & Compressor. Quite honestly the only point of putting this sub in, is to cut down on my costs...2.00 a foot for 6-3 copper on a 50' long building adds up fast per circuit. By putting in the sub, I can save over 200.00 of wiring. I could always put the lighting and other recept's into my "main" subpanel already installed...no biggie there. I hadnt done it yet for the simple fact of if theres a sub 10' away, why not use it instead of the one 30' away But now your making me thing I might be wise to just pull the lighting and the normal Recept's into the Main...this sub will be solely for the big items like Welder/Compressor/etc.

 

[Alchymist]

I dont "Have" to use flex...I just figured, by the time I bought all the EMT, Fittings & Elbow's cost wise Im not ahead and I've got a PITA to install...sure the Flex doesnt look as elegant when installed, but once I sheath my attic room upstairs, nobody will ever see it.



LOL, you got a point (and I'd like to see one guy use all those at once too)...I do have a stick already (Maxstar 150), of course I cant say I own any other welders at this time, but I would like a Millermatic 212 at some point and a Thermal Dynamics Cutmaster 52. The only 2 things I can see running at once would be the Plasma & Compressor. Quite honestly the only point of putting this sub in, is to cut down on my costs...2.00 a foot for 6-3 copper on a 50' long building adds up fast per circuit. By putting in the sub, I can save over 200.00 of wiring. I could always put the lighting and other recept's into my "main" subpanel already installed...no biggie there. I hadnt done it yet for the simple fact of if theres a sub 10' away, why not use it instead of the one 30' away But now your making me thing I might be wise to just pull the lighting and the normal Recept's into the Main...this sub will be solely for the big items like Welder/Compressor/etc.

If it works out length wise, you can always run a 10-3 to a small sub panel and run all your lights from that. Say a 6 position panel would allow 6- 15 or 20 amp lighting circuits, should be plenty, and save on the smaller home runs.

 

[walrus]

If its only good to 55A, why is it legal/safe to put it on a 60A breaker? No code here...so safety/doing it right is my only concern.

Of course there is code there, Maine has an inspector in the "county", His name is Patrick