Control Panel: Too Much Power?

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mosstradamus

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Has anyone used separate 240V and 120V power sources/circuits as inputs to a control panel?

In an effort to make the design for my new E-Herms as complicated as possible, I was thinking about using two separate power sources (separate cicuits) to provide the greatest amount of flexibility. I currently have 30A 240v outlet in my garage, in addition to my 120V (GFCI on both 120 & 240). My current set up is a 240v/4500w keggle with PWM control.

I would like to run a BCS, one pump and one of the 120v/2000w elements off of the dedicated 120 circuit, and use the the 240v side to run one of the 5500w elements and a pump(using one leg of the 240). The BCS would control both sides with everything in one control panel.

HLT : 120v/2000w and 240v/5500w elements
BK1: 240v/5500w element
BK2: 120v/2000w element

Being able to run 5500w and 2000w elements at the same time would allow me to:

Spend a lot of money on a capability I may not use
Heat the HLT quickly with 2 elements at the same time
Boil a 12 gal(240v) & 6 gal (120v)batch at the same time
Boil 12 gal with 240v while maintainig HERMS with 120v
Sous Vide somewhere other than my basement using 120v only

I have looked through a ton of P-J diagrams and haven’t found anyting similar to what I am considering. Has anyone seen this done anywhere? Is there a good reason I should abandon this plan and just do a standard design?
 
As long as you keep the circuits (lines/neutral) separated, I don't see why this wouldn't work. Just build two systems but house them in the same control panel?
I'm sure there are some Code concerns to deal with here, but I am not an electrician....
 
From a theoretical standpoint, I can't see why it wouldn't work, as long as you keep the systems separated as Ryan George said. Would it be easier to swap the 30A 240V to 50A? Can you confirm what wire size was installed? How far of a run is it? Or, have you already considered all of that and decided that going for the most complicated setup possible was your cup of tea?
-Kevin
 
Ryan George...thanks, keeping "both sides" separate is definitely on at the very top of my list.

Kevin... It is a short 10 gauge run, about 6 feet from the breaker box. I am using the inline GFCI extension cord that is rated at 240v/30amp.

I am currently renting a house, and would prefer to work with what I have. Having lived in 11 different places in the last 22 years, it would be nice not to have to pop in new breaker and a new run every time, but it may be cheaper & easier than having a complicated control box.
 
If it's a rental, you have to weigh that. On the one hand, popping out the breaker and throwing in a 50a and running a section of 6ga wouldn't be too hard, but it would require you to modify the existing setup more than you may want to do. As far as moving and using your setup elsewhere - you have just as much chance of your next house having a 50a circuit as a 30a and a nearby 120, right? Or maybe not, if you've had experience with the 30a 240v plugs before.

An important question that wasn't asked - is your 30a outlet in the garage 3 prong or 4 prong?
-Kevin
 
Kevin,
It is currently 4 wire to the outlet.

Switching to an entirely 240 based system by installing a new breaker and spa panel may be cheaper than the extra wire, connectors, SSRs and heating element of a "dual system". Running larger elements in all the vessels also changes my options on doing closely staggered large batches.

Here is a pic of what I have to start with....the 3 kegs on the right are cut upside down (sanke side down). The keg on the left is what I currently use with a PWM ammo box.

Once I settle on a the control box configuration, I can figure out which kegs, pots or coolers to use.


Chris

Garage.jpeg
 
I have 50A to my HLT, 30A to my BK and a 20A/120V for pumps etc... I have wired many non-brewing control panels with multiple power feeds. You won't have an issue as long as you keep everything separated as suggested.
 
I am considering doing something similar so that I can run elements in my BK and HLT at the same.

I'd like to use my 120V 15a source to power my HLT and my 240V 30a source to power my BK.

Wouldn't there be an issue with grounding the box if I have 45a coming into it and the max AWG ground that I have is 10AWG (although there will also be a 14AWG there)
 
I am considering doing something similar so that I can run elements in my BK and HLT at the same.

I'd like to use my 120V 15a source to power my HLT and my 240V 30a source to power my BK.

Wouldn't there be an issue with grounding the box if I have 45a coming into it and the max AWG ground that I have is 10AWG (although there will also be a 14AWG there)

Wouldn't the 120V and 240V be completely separate in the panel, grounded separately, with 14AWG and 10AWG respectively?
 
I am considering doing something similar so that I can run elements in my BK and HLT at the same.

I'd like to use my 120V 15a source to power my HLT and my 240V 30a source to power my BK.

Wouldn't there be an issue with grounding the box if I have 45a coming into it and the max AWG ground that I have is 10AWG (although there will also be a 14AWG there)

This is a bit tricky... Here's a non-electrician's take:
I would be tempted to omit the 14 AWG ground to ensure that your 30A source wouldn't try to ground out through it (thus burning it up). This is assuming you NEVER plug the 15a circuit in without the 30a circuit present. It is unlikely that both your 15a and 30a circuits have a ground fault at the same time.

But maybe the more grounding the better, so use both? Or run a dedicated grounding clamp of sufficient gauge to a good known ground source with acceptable current carrying capacity?
 
Yes, I was not clear. I meant could not the 15A circuits use 14awg and the 30A circuits use 10awg until they are bonded together at the panel? My logic would be that my home wiring runs to a common ground, and I base the the gauge of the ground in any individual circuit based upon the breaker in that circuit, not the highest current breaker in any circuit in the home.

Does this make sense? Sorry for the confusion.
 
You've got 90A going into one control panel? How do you have your grounds set up and what gauge wire are they?
 
You've got 90A going into one control panel? How do you have your grounds set up and what gauge wire are they?
I used 3 GFI breakers. It's 10 ga wire. Each wire carries a max of 30A. I thought about using 1 big breaker until I went to HD and saw what 6 ga wire looked and felt like! Not sure what you mean about setting up grounds. I have one ground wire coming from the panel.
 
If you have three GFI breakers, that means that there are technically three 10awg grounds coming out of your box, correct?
 
If you have three GFI breakers, that means that there are technically three 10awg grounds coming out of your box, correct?

If you use cable like romex for the feeds, you need to carry an equipment ground in each cable. If you run the feeds in conduit, you size the equipment ground (only one is required) for the largest circuit breaker. All simply get tied together and bonded to the control panel.
 
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