wiring subpanel for future expansion

I have this subpanel from my old house, for 220V woodworking tools. I had 2x 120V circuits, plus a 15A 220v and a 20A/220V. That leaves a single slot open.

I plan to run the branch wiring soon, and I have plans to build a 30 A e-brew setup. I have started working on the keggle and have the 5500 W ULD element, but no other supplies for that side of the project.

Is there a slim 200V breaker that spans both hot legs without taking up so much room in the panel?

So given what I currently have, what is the cheapest way to get 30 A e-brew setup into this panel?

I used 12A branch wiring for the 15A and 20A 220V circuits. Is that AWG too thin to run 30A? The run would be about 15' max from the garage to the driveway.

What is the gauge of the wire feeding the panel? For 30 amps you need 10 AWG wire and it doesn't look any bigger than that. If it is 10 AWG or bigger you could install a bigger panel pretty easily. If it is only 10 AWG, the brewery is the only thing you should run from that panel.

Any 240v breaker will take up two slots

I've seen single pole tandem breakers that take up only one space but I have not seen a double pole breaker that takes up only one space.

14ga for 15A
12ga for 20A
10ga for 30A

Short distance makes no difference. It's the insulation that overheats and melts when the current capacity is exceeded.

Looks like a GE or similar sub panel.

Lowes shows a SlimLine double pole breaker

http://ts2.mm.bing.net/th?id=H.4770648911774057&pid=15.1

Sometimes these sub panels wont let you install a Slim breaker (the CB mounting or tabs prevent their use)

Keep adding circuits and you'll need 50A feeding it.

'da Kid

Well after zooming in on your panel, I see it's a Square-D
Still very doable.

You'll need a 'quad' breaker.



Lowes again shows they carry them.

You'll have to research to see if it fits.

Square-D makes two lines of panels.
Commercial and Homeline

'da Kid

The wire you show wired in your OP looks WAY undersized . . . . . .
Hopefully it's on a 20A breaker or less in the main panel.

Be safe,
'da Kid

The10mmKid said:

Well after zooming in on your panel, I see it's a Square-D
Still very doable.

You'll need a 'quad' breaker.

Lowes again shows they carry them.

You'll have to research to see if it fits.

Square-D makes two lines of panels.
Commercial and Homeline

'da Kid

Click to expand...

Whoa. That quad breaker is awesome. You learn something every day.

I've got 8/3 (with 10 gage ground) feeding the panel

so I could replace the current 20A breaker with a 20/30 quad as shown? And run the 30A line to a spa panel?

More than likely.

'If the breaker fits, you must acquit'
Buy one and try it.
Square-D will be built right to keep you from using the wrong style breaker.

What type of cable is that "8/3"? UF?, RHW?, RHW-2?

Your pic shows conduit. Run single strands of THHN . . . . good for 50Amps
(really 55A, but try finding that breaker)
A #10 ground is appropriate

'da Kid

Piggyback breakers are bad about overheating and tripping before a normal one. If you gotta use it then you gotta.

Also the insulation does melt but take it from an electrician and volunteer firefighter the copper will melt and spark if over loaded. THHN is only a type of insulation and doesn't have any doing with the amp rating of the wire. Wire size, length of run, and item being fed determines what it will carry.

Besides I'd be more interested in the main panel that sub is feeding from. If its only a 200 amp, your house draws 190 amps, that means you only have 10 amps to spare before the main is tripping all the time. You can run 4/0 cable to that sub but its not gonna make everything upstream magically increase to meet current demand.

neo71665 said:

If its only a 200 amp, your house draws 190 amps, that means you only have 10 amps to spare before the main is tripping all the time. You can run 4/0 cable to that sub but its not gonna make everything upstream magically increase to meet current demand.

Click to expand...

True, but it would be pretty rare to have loading that high. If that's a common situation then a single 200A panel probably isn't the right thing to have anyway.

This subpanel is being fed with a 50A breaker. The 8/3 feeder cable is Type NM-B

Trying to figure out my options. If I pull out the current double slimline 120V/20A, I will have 2 slots open. I can put the quad breaker in those two slots, but that only gives me a single 120V/20A circuit (in addition to the 240V/30A circuit)

I will never be brewing and woodworking at the same time, so the total load on the 240V stuff is irrelevant. But one of the 120V circuits is used for my beer fridge, and I need to compressor to cycle on as needed, with other small tools and lights on the same circuit if I consolidate to a single 120V/20A circuit.

twd000 said:

This subpanel is being fed with a 50A breaker. The 8/3 feeder cable is Type NM-B

Click to expand...

Be careful of that 50A. 8/3-W/G is usually derated to 40A.

From SouthWire.com
"Type NM-B (nonmetallic-sheathed cable) may be used for both exposed and concealed work in normally dry locations at temperatures not to exceed 90°C (with ampacity limited to that for 60°C conductors) as specified in the 2011 National Electrical Code."

OK, you will loose a full size single 20A breaker; opening a spot for the 'quad'.
But you'll gain (2) 20A-single and (1)30A/2-pole.
The outside breakers work independent of any other breaker in the quad.

You can even use two quads if you want.
15A-2x30A-15A and then 20A-2x30A-20A

(This is assuming the quads will fit your panel)

So far, all your options are still on the table. Just be careful loading that 8/3 past 40A. There is some safety factor built in, but any extended duration full load is going to heat up that feed wire.

Be safe,
'da Kid

A quad and two tandems would be the max number of circuits assuming you only need one 240V circuit. That way you could have six 120V circuits and one 240V.

sweet. sounds like the quad will get me what I need

I'll never get to 40A draw. The woodworking machines have large induction motors that pull a lot of amps on startup then quickly settle down to 6-8 Amps

The largest draw I'll have is running my ULWD element plus the fridge, and that should be under 30 A

whoaru99 said:

True, but it would be pretty rare to have loading that high. If that's a common situation then a single 200A panel probably isn't the right thing to have anyway.

Click to expand...

More common than you think, lowest bidder usually gets the cheapest and barely big enough products to get the house done. Often builders are more than happy to save money everywhere they can.

I understand about lowest bidders but presumably they still have to be built to the spec, NEC, and pass inspection.

a longshot followup question: is there such thing as a quad breaker that includes a GFCI, so that I wouldn't have to add a spa panel downstream of this sub-panel?

twd000 said:

a longshot followup question: is there such thing as a quad breaker that includes a GFCI, so that I wouldn't have to add a spa panel downstream of this sub-panel?

Click to expand...

Why not put the GFCI upstream? Replace the 50A breaker in the main panel with a 50A GFCI breaker.

ChuckO said:

Why not put the GFCI upstream? Replace the 50A breaker in the main panel with a 50A GFCI breaker.

Click to expand...

I would be open to that option. Assuming I wouldn't be prone to false-tripping due to various garage loads turning on an off while I'm brewing?

I have a Siemens 50A double pole GP-type in that slot? What is the cheapest replacement?

I'm seeing $100+ on the breaker vs. $56 on the spa panel w/ breaker

http://www.homedepot.com/p/Eaton-50-Amp-Spa-Panel-BR-Type-BR50SPA/100206043#.UkY7VlO6bTo

I went to an electrical supply house that sells both wholesale and retail and purchased one for my Siemens panel for about $85.00 a couple of years ago. Look further than just at big box hardware stores.

If you aren't having problems tripping your existing breaker now you shouldn't have problems with a GFCI breaker. If you do have it trip on a ground fault then you have some equipment that should be investigated for grounding problems.