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Old 05-02-2011, 05:17 PM   #1
ikonis
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Apr 2009
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I'm converting my rig from stove/e-rims to a full 240V e-HLT, e-RIMS, and e-Kettle build.
Just been racking my brain on how many Amps I'd be drawing when 2 elements are on

I'm planning on using 3500W 240V elements in the kettle and HLT.
So those would pull 14.58A at 240V.

In my RIMS tube, I was hoping I could use my current 2000W 120V (running at 120V of course).
That's 16.67A at 120V.

Now the question arises; If I'm using the HLT and RIMS tube at the same time, is that going to pull 31.25A (14.58A+16.67A) from the circuit? If that's the case, I would need to install a 40A GFI breaker, and #8 wire. Which I can do fine, there is no existing circuit for this build as of yet.

I can of course use smaller elements, but was hoping I could get away with using the sizes I previously said.

I am planning on only ever doing 4-5gallon batches, so yes, I know it may be completely overkill to do this at all. But that doesn't matter to me. DIY FTW.


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Old 05-02-2011, 06:38 PM   #2
audger
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., Connecticut
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just so you are aware- i have a "2000 watt" 120v heating element, which i expected to pull about 16-17 amps like you have there, but in reality i measured it at between 14.8 and 15.3 amps, so the ratings are perhapse the maximum possible current draws. ymmv.

edit- nvm the rest im dumb- thinking 3 phase



 
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Old 05-02-2011, 06:50 PM   #3
ikonis
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Quote:
Originally Posted by audger View Post
just so you are aware- i have a "2000 watt" 120v heating element, which i expected to pull about 16-17 amps like you have there, but in reality i measured it at between 14.8 and 15.3 amps, so the ratings are perhapse the maximum possible current draws. ymmv.

edit- nvm the rest im dumb- thinking 3 phase
3 phase would be nice lol
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Old 05-02-2011, 07:35 PM   #4
Lechien
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If both were on at the same time it would draw 14.58 on on leg and 31.25 on the other leg.

Reason: spelling

 
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Old 05-02-2011, 08:14 PM   #5
ikonis
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That doesn't seem right. 31.25A?
In my situation, I'd only have 1 of the 240v elements on at a time. And when boiling, the HLT nor the rims would be on
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Old 05-02-2011, 10:49 PM   #6
Lechien
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Quote:
Originally Posted by ikonis View Post

Now the question arises; If I'm using the HLT and RIMS tube at the same time, is that going to pull 31.25A (14.58A+16.67A)
HLT ([email protected])will draw 14.58 on two legs
RIMS ([email protected])will draw 16.67 on one leg

if HLT and RIMS used at the same time 14.58A on one leg and 31.25 on the other leg.

if only HLT ([email protected]) will draw 14.58 on two legs

if our only boiling ([email protected]) will draw 14.58 on two legs

 
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Old 05-02-2011, 10:55 PM   #7
ikonis
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Quote:
Originally Posted by Lechien View Post
HLT ([email protected])will draw 14.58 on two legs
RIMS ([email protected])will draw 16.67 on one leg

if HLT and RIMS used at the same time 14.58A on one leg and 31.25 on the other leg.
Wait wait. What about the neutral wire for the 120V... wouldnt that carry the return for the 120V element?

I mean regardless, a 30A breaker wouldn't suffice at these wattages.
but 3000W 240V and 1500W 120V should be pulling 12.5A each respectively. Netting 25A total...

Edit:
I will be pulling new 10/3 romex and installing a GFI breaker if this helps calculations.
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Old 05-02-2011, 11:08 PM   #8
Lechien
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Quote:
Originally Posted by ikonis View Post
Wait wait. What about the neutral wire for the 120V... wouldnt that carry the return for the 120V element?

I mean regardless, a 30A breaker wouldn't suffice at these wattages.
but 3000W 240V and 1500W 120V should be pulling 12.5A each respectively. Netting 25A total...

Edit:
I will be pulling new 10/3 romex and installing a GFI breaker if this helps calculations.
240v elements draw on each leg A & B
3000W 240V will draw 12.5A on leg A and 12.5A on leg B
120v elements will draw on one leg
1500W 120V will draw 12.5A on which ever leg (A or B)you put it on
Total draw for both would be 12.5 Amps on one leg and 25 on the other

Maybe someone else could explain it better tham I can.

 
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Old 05-02-2011, 11:18 PM   #9
ikonis
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So I would need a 40A+ breaker? Or am I just misunderstanding how a double pole breaker works
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Old 05-02-2011, 11:27 PM   #10
P-J
HBT_LIFETIMESUPPORTER.png
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May I suggest that instead of a 2000W 120V element, just get a 2000W 240V element. Look for a "Rheem SP10869GL" element.
Here is a link to a source. bostonheatingsupply.com Rheem SP10869GL

This would put you at 14.6A for the 3500W and 8.3A for the 2000W or a total of 23Aħ - plus pumps et.al.



 
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