60amp vs 30amp vs whatever - Electrical Question

[MrShake]

Ok all you DIYers here on HBT. I've got a proposed solution to my eHERMS setup, and I'm wanting any advice you can give.

Please bear in mind these 2 stipulations:

1. I do not want to hard wire the stand to the electrical box. I want to be able to unplug
2. I want to minimize the number of electrical cords. Ideally, 1 220 cord and 1 110 cord to the control panel.

With those stipulations in mind, and running 2 220 elements, here is my current plan to power my eHERMS:

In my house 200amp service box, I'll have a 60amp double pole breaker and a 20 amp single pole breaker.
I'll run 6/3 and 12/2 to the garage.
The 6/3 will feed a 60amp GFCI spa disconnect giving me GFCI protection on the 60 amp circuit as well as a 110 15a leg and breaker
The 12/2 will feed a number of outlets in the garage
The Brew Cart will have 2 cords and will plug into receptacles on the wall by the disconnect.
The 60 am 6/3 will go to a distribution block where it will break into appropriate guage wire for 30 amp lines to each heating element.
Between the distribution block and the heating element I will place a fuse holder and 2 30amp 220v time delay fuses. These fuses will protect the 30amp lines, and the 60amp GFCI panel will protect the entire cart via GFCI and/or if both elements are running.

Thoughts?

 

[The Pol]

Sounds pretty standard, I dont see a problem with it at first glance

 

[Ohio-Ed]

With a 60 amp breaker and 60 amp GFCI, you are going to need to run 4/3 instead of 6/3. 60amp plugs & receptacles get VERY expensive and hard to find. I would suggest you try to find a way to do it on a 50amp breaker/gfci.

Ed

 

[CodeRage]

To expound on what Ohio Ed said. #6 THW is good for 65 amps but #6 romex is only good to 55.

I would put the 60amp gci in as your main breaker, but in a 20 amp single pole 12/3 for your outlet service and 2 30 amp double pole breakers in for the brewery with 10/4. The twist locks are much cheaper for 30 amps versus 50/60. If you're going to run 2 cords, might as well be 2 30 amp 240v Services. You can split them in the control box as needed for 110.

 

[MrShake]

To expound on what Ohio Ed said. #6 THW is good for 65 amps but #6 romex is only good to 55.

I would put the 60amp gci in as your main breaker, but in a 20 amp single pole 12/3 for your outlet service and 2 30 amp double pole breakers in for the brewery with 10/4. The twist locks are much cheaper for 30 amps versus 50/60. If you're going to run 2 cords, might as well be 2 30 amp 240v Services. You can split them in the control box as needed for 110.

60amp gci in the main breaker box is a deal killer. the QO 60 amp gfci for my square d box is list price 400 bucks, found it online for the low-low price of 175. So its cheaper even to put a 60 regular in and run to the 60 spa disconnect.

I could do this at 50 amps, but wouldn't have much overhead, thats why I went with the 60 amp setup

 

[Ohio-Ed]

60amp gci in the main breaker box is a deal killer. the QO 60 amp gfci for my square d box is list price 400 bucks, found it online for the low-low price of 175. So its cheaper even to put a 60 regular in and run to the 60 spa disconnect.

I could do this at 50 amps, but wouldn't have much overhead, thats why I went with the 60 amp setup

If you can get your requirement below 50amp... you can put a 50 amp breaker in the panel and run to the 60amp gfci disconnect. Then from the spa disconnect toy your rig. You then have 50amp over current protection AND gfci protection.

You are going through the same kind of thinking process that I did a few weeks ago. I wanted to be able to run everything on my rig at the same time. After pricing out some components, I decided I can get by with only running 2 of three elements at a time to get below the 50amp point.

 

[CodeRage]

Ouch, that is a hit for sure on the 60A GFCI. Honestly, if you need more than 50A you are wasting power. (Unless your doing something like 20gal batches.) For 5 and 10 Gallons 50A is more than enough. Hell, I run a 5500W BK and 4500W RIMS element on a 30 AMP service, they are interlocked so I can only run one at a time but It hasn't been an issue at all.

I would be happy with a 4500W BK element and a 2000W RIMS. That gets me under my 30A service running them together while running a march pump on each leg. (Before any one goes busting my balls about the NEC 80% Continuous Load rule look up their definition of continuous load first!)

If you were running a herms, a 5500 in the BK and HLT (4500 is sufficient for 5-10 gal) running together is under 50A with a couple of Amps to spare. Check your line voltage too. Mine is closer to 220 which means the elements use 9% less current than the power rating of the elements state. Why you would need to run the HLT and BK at the same time is a little beyond me, because 5500W is no slouch boiling 8 to 9 gallons with a boil off rate greater than 2gal an hour at full tilt.

Honestly 30A is plenty for 5-10gal. 50A is nice to have, anything bigger is overkill needed for 10gal pilot batches. You can put that money to more brew gear or fab tools

I really look forward to seeing what you come up with brother.

 

[MrShake]

Ok, I think I'm starting to settle on reality here, here's my logic, please correct any bad thinking:

50amp Breaker at Main Box
to
6/3 romex
to
60amp GFCI Spa Disconnect Panel (36 bucks at home depot by the way)
to
50amp range cord
to
Control Panel
to
Distribution block
to
2 30 amp fuses
to
each element


That sound right? 25 amp fuses are a posibility as well... since...

4500watt element in the HLT is 20.4545455 amps
5500watt element in the BL is 25 amps

Thoughts?

 

[CodeRage]

I get 18.75A for 4500 and 23A for 5500. Are they stamped 240V or 220V? Looks like you did your math using 220.

I would use 10 AWG to supply the elements. Put 30A fuses at the beginning of the 10AWG runs to protect the wire from over current. You can get 10/4 S00 cord from the big box stores for a little over 2 bucks a foot. Thats what I used for mine.

 

[MrShake]

yea, I did my math at 220.... this is sounding more and more reasonable, and meets all my criteria!!

 

[MrShake]

Just to check my logic again... here are the fuse parts I'm looking at... all mcmaster.com

7687K12 - 2 pole fuse holder

71385K531 - 30amp 250v ceramic tube fuse

 

[mmurray]

Not to throw a monkey wrench into the deal, but what about 2 50amp services to your Herms system? you could buy the cords from a local motorhome lot or supply store and water proof... like the yellow one below.

Then have 2 panels mounted on your wall like so...

in your panel on your Herms system you could have 2- 30amp and 2- 20amp feeds (1 from each line.)

Just figured buying a 50amp RV power cord might be an easier and possibly cheaper source for your cords... then just run 6/3 to each panel for each cord.

Just my .02

 

[MrShake]

Not to throw a monkey wrench into the deal, but what about 2 50amp services to your Herms system? you could buy the cords from a local motorhome lot or supply store and water proof... like the yellow one below.

Then have 2 panels mounted on your wall like so...

in your panel on your Herms system you could have 2- 30amp and 2- 20amp feeds (1 from each line.)

Just figured buying a 50amp RV power cord might be an easier and possibly cheaper source for your cords... then just run 6/3 to each panel for each cord.

Just my .02

I like the cord idea!! may have to check that out.

However, 2 50 amp circuits is getting back to the original problems.. specifically, cost and over fusing

running 50 amps into the control panel and then running a 30 amp product doesn't give you any protection of that 30 amp product shorts and burns up wires... hence the fuses.

And, 2 50 amp runs would mean 2 runs of 6/3 wire... EXPENSIVE and way more power than I need

I LOVE the cord idea though!

 

[Budzu]

How about just a whole subpanel in the garage? You could up your service for any future needs, and probably save some cash by wiring from your main panel to your sub with 4 wire aluminum. The 2-2-2-4 gauge is like 1.60 per foot. This would supply everything, 240 and 120v.

In your subpanel you can have your gfci breaker, and space for 2 20 amp single poles.

This would require a regular 100 amp breaker in your main.

 

[mmurray]

Good Idea... but stay away from aluminum wire.

http://www.faqs.org/faqs/electrical-wiring/part2/section-16.html

The main problem with aluminum wiring is a phenomenon known as "cold creep". When aluminum wiring warms up, it expands. When it cools down, it contracts. Unlike copper, when aluminum goes through a number of warm/cool cycles it loses a bit of tightness each time. To make the problem worse, aluminum oxidises, or corrodes when in contact with certain types of metal, so the resistance of the connection goes up. Which causes it to heat up and corrode/ oxidize still more. Eventually the wire may start getting very hot, melt the insulation or fixture it's attached to, and possibly even cause a fire.

 

[mmurray]

I like the cord idea!! may have to check that out.

However, 2 50 amp circuits is getting back to the original problems.. specifically, cost and over fusing

running 50 amps into the control panel and then running a 30 amp product doesn't give you any protection of that 30 amp product shorts and burns up wires... hence the fuses.

And, 2 50 amp runs would mean 2 runs of 6/3 wire... EXPENSIVE and way more power than I need

I LOVE the cord idea though!

The 6/3 should run between $1.75 and $2.00 per foot (I don't know how far of a run you have.)
Those 2 50amp RV Boxes are around $35 each.
Then I'd buy 2 60amp shop panels (no price listed) one for each plug to supply power to.

Then have a 30amp 2 pole breaker and a 20 or 2 10amp single poles... in each box.

The only thing left would be to install an inlet on the top of each panel to accept the RV cord... http://www.discountmarinesupplies.com/Marinco_Inlets-MARINCO_STANDARD_POWER_INLET_50A_125_250V.html

The wire and cords are going to be the expensive part of this set up.

 

[whitescout]

Depending on the spa box from home depot.... If it is the GE box labeled as Midwest, you have several options. The box is basically a 100 amp subpanel. It comes with 1 50 or 60 amp GFCI breaker depending on which one you buy. Then, it comes with places to add 4 more circuits. You could feed the panel with a 100 amp breaker, and then use the 50 or 60 amp GFCI as you see fit, and also run smaller GFCI breakers in it for your needs.