E-Panel Wiring/Breaker Question

I'm building out a Kal/EBrew E-HERMS panel (posts on the build-out coming soon).

Question on wiring.

If I have a 30a breaker in my house supplying 220 to my brew panel. Is there a need to run anything bigger than 10ga in the panel? In the wiring diagram I have my 10/4 coming into a contactor (for key switch) and then to a 25a breaker before sizing down to 10ga for the remainder of wiring.

However, I've seen pictures of others that use 6ga out of the contactor BUT go to a DIN block and downsize to 10ga before going to the breaker. I understand that 10ga is rated for 24a, so my house breaker might not trip on a brew panel "overload". However, since the 10ga still goes through the 25/15a breakers...would I be ok either way? Is there even a need for 6ga?

See picture below of wiring diagram, with my drawn-in block with 6ga entering/10ga leaving.

Thoughts?

10 ga is fine for the high amp stuff assuming you have 5500w elements. If you have higher wattage elements you will need lower gauge wire (eg 8). This is because 5500w elements only draw ~22 amps each, and the pumps around 1 each. Which puts you at 24 - 25 amps max, within the tolerances of the 10 ga wire and 30 A breaker. Fuses and/or additional breakers in the panel can't hurt.

The 80% derating does not apply to any brewery build I have seen. #10 is good for 30A. Size the wire for the breaker or fuses ahead of it. If you tap off of the #10 to a 15A breaker or fuse, you can then use #14.

The only reason I can figure someone would run 6ga is to "future proof" their brewery. You can always swap out the breaker. Much harder to swap out Sheetrock, etc.


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I have a 30A control panel and a 30A breaker. While 10ga is required between the two, I use 6ga just in case I ever want to upgrade to a 50A control panel.

The increased cost of installing 6ga in the wall instead of 10ga is somewhat negligible in the grand scheme of things. Like heckles said, changing wiring in the wall is not easy/quick/cheap.

Kal

Thanks everyone...

kal said:

I have a 30A control panel and a 30A breaker. While 10ga is required between the two, I use 6ga just in case I ever want to upgrade to a 50A control panel.

Click to expand...

Luckily my run is from a subpanel in the basement to my garage with exposed joists (about 20 ft), so easy to upgrade my 10/4 to 6ga later if I ever wanted.

Wanted to clarify my question too... given a 30A breaker in the house, 10/4 in the wall and a 25A breaker in the brew panel, putting 6ga IN the brew panel (anywhere) would seem like overkill. I did up until the breaker, but after that, I should never draw over 25A.

To upgrade, I would need a 50A in the house, 6ga in the wall and by that point, I'm building a new brew panel anyway since my layout is off.

Fair?

Yup!

However - If you know you're going to upgrade to 50A eventually (not sure if that's the case), you might as well put 6/4 in the joists instead of 10/4 now and then replace it later with 6/4. That'll cost less.

Kal