Heating Element / Controller Question

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NWMushroom

NWMushroom

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Quick question.

I am looking at heating elements/controllers that will plug into my stove outlet.

Looking at my stove outlet, I have a four prong socket (the stove plug only has three prongs). The socket is printed with '250v 50A'. When I look in the circuit/breaker box in the house the circuit breaker for the stove is marked 40A.

The controller and 4500W element I am looking at have the following requirements:

220V 30A service. Includes a 6 ft power cord with either a 3-wire plug (NEMA 10-30P) or a 4-wire plug (NEMA 14-30P).

Is this going to be OK for my stove outlet?

Thanks in advance.
 
The short answer is no, because the 40a breaker is oversized for the 10 gauge wire. You would need a 30a breaker so that it would trip if the 10 gauge wire overheated.

You should also think about GFCI protection.
 
Among your alternatives:
1) Replace with a 30a breaker, although that may not be sufficient for your stove.
2) Find/build a controller that uses wire (8 gauge) and fixtures rated for 40a or more (readily available outlets and receptacles will be rated for 50a).

I'm assuming your current receptacle is NEMA 14-50?
 
Ummmm.... pass!

Here is a picture of the stove outlet:

88550073.png


Here is a picture of the dryer outlet:

66111836.png


Here is a picture of the two breakers (dryer on left, stove on right).

67774385.png


I am a renter so can't install or change anything.

Am I out of options?
 
OK, so what does that mean in terms of my ability to come up with an electric brewing rig?

My apologies if it's obvious - I am not electrically inclined (or skilled)!
 
NWMushroom said:
OK, so what does that mean in terms of my ability to come up with an electric brewing rig?

My apologies if it's obvious - I am not electrically inclined (or skilled)!
Click to expand...
You have the power source. All is ok.

Now all you need to do is define what you want for your set up. Tell us what controls you want in place and how you want to run your rig.

I can help with the right info.

P-J
 
Youre only gonna be drawing around 20 amps so youre fine with the breaker. Oversizing is fine, not undersizing.
 
jeffmeh said:
The short answer is no, because the 40a breaker is oversized for the 10 gauge wire. You would need a 30a breaker so that it would trip if the 10 gauge wire overheated.

You should also think about GFCI protection.
Click to expand...

mikeysab said:
Youre only gonna be drawing around 20 amps so youre fine with the breaker. Oversizing is fine, not undersizing.
Click to expand...

So 1 says yay, 1 says nay!

Help!!
 
Typically, you want the breaker to be sized to match the wiring in your walls. Once you get to an outlet, the requirements to have matching sized wiring is impossible to maintain - think of your house - you have various outlets throught your house, but you don't size match all your plugs and cords once you plug something in. I believe the general theory is that you'll notice a smoldering plug or cord much sooner (and much easier) than you would a smoldering wire inside your wall.

So, that being said - using a lower power draw plug is not an issue.

At least, that's my thought. I'm not an NEC master or certified electrician, and only have worthless advice to give.
 
As PJ said, you have a workable power source - you just need to choose the right components to get that power from the outlet (probably through a controller of some sort) and to the element.

Let us know what kind of setup you want... 3 vessel, 2 vessel, eBIAB, full control with a PID, throttle control with a rheostat or PWM, etc. People will jump in and give you the advice you're seeking.

Basically - you want to go from that outlet to a protective device. The usual arrangement is via a spa panel with a GFCI breaker. Then from the spa panel to a controller, then from the controller to the kettle. You most likely won't find an off-the-shelf solution, but try calling/emailing High Gravity or one of the other vendors and see if they are willing to wire it for you. Otherwise, you can still use a pre-built system; it will just require some minimal wiring for you to put together the spa panel, then plug the off-the-shelf controller into the appropriate receptacle that you have installed on the spa panel.
 
mikeysab said:
Youre only gonna be drawing around 20 amps so youre fine with the breaker. Oversizing is fine, not undersizing.
Click to expand...

This is incorrect. The purpose of the breaker is to trip and cut power if a situation occurs where there is more current than the wiring can handle without overheating and catching fire. If he has 10awg wiring, it is only rated for 30a. The breaker will not trip until 40a. You can safely undersize breakers for the wiring. You can safely oversize plugs and receptacles.

If it sounds counter-intuitive, think about it as the 10awg wire is undersized for the 40a breaker.
 
Also, from your pictures, those are NEMA 10-50 outlets, and if they are wired to purpose they would have Hot-Hot-Neutral, with no true ground. That would need to be verified, because it could be Hot-Hot-Ground, but normally that would be NEMA 5-50.

It is all still doable, but not likely with an "off the shelf" product, unfortunately. P-J and others can definitely get you there, if you are game.
 
Thanks for everyone's input. I have emailed High Gravity Brew to see if they can put something together for me based on what I've learnt here. I am just not comfortable with wiring or creating my own controller, etc - so may have to stick with the propane for a while longer!
 
NWMushroom said:
Thanks for everyone's input. I have emailed High Gravity Brew to see if they can put something together for me based on what I've learnt here. I am just not comfortable with wiring or creating my own controller, etc - so may have to stick with the propane for a while longer!
Click to expand...

Do not give up I just built a 3000 watt ebiab 110 system. As long as there is HBT there always seems to be a way.
 
jeffmeh said:
This is incorrect. The purpose of the breaker is to trip and cut power if a situation occurs where there is more current than the wiring can handle without overheating and catching fire. If he has 10awg wiring, it is only rated for 30a. The breaker will not trip until 40a. You can safely undersize breakers for the wiring. You can safely oversize plugs and receptacles.

If it sounds counter-intuitive, think about it as the 10awg wire is undersized for the 40a breaker.
Click to expand...

So what do you have to say about an 18awg lamp cord, rated for ~6 amps, plugged into a wall outlet on a 15 amp circuit? The lamp has a warning not to exceed 75 watts. It should never pull more than 1.6 amps.

How is that different from matching a power cord to a heating elements max draw as long as you stay under the rating of the circuit breaker, and thus the wiring is the wall?
 
jeepinjeepin said:
So what do you have to say about an 18awg lamp cord, rated for ~6 amps, plugged into a wall outlet on a 15 amp circuit? The lamp has a warning not to exceed 75 watts. It should never pull more than 1.6 amps.

How is that different from matching a power cord to a heating elements max draw as long as you stay under the rating of the circuit breaker, and thus the wiring is the wall?
Click to expand...

What I say to that is that your breaker is not protecting the 18awg wire, but if you were to experience an anomaly like a short, your bulb will blow and open the circuit well before you reach the maximum rating of the wire. The bulb acts like a fuse, and when it blows it may even trip the breaker.

Similarly, the OP could use his 40a breaker, and use a panel wired with 10awg wire, if he put a 30a fuse or breaker in the panel to protect the wire.

We don't size the wire based upon the "normal" amperage draw of the equipment, we size it to match the breaker (or we fuse the equipment accordingly) so that under catastrophic circumstances the breaker (or fuse) will trip before the wire catches fire.
 
jeffmeh said:
What I say to that is that your breaker is not protecting the 18awg wire, but if you were to experience an anomaly like a short, your bulb will blow and open the circuit well before you reach the maximum rating of the wire. The bulb acts like a fuse, and when it blows it may even trip the breaker.

Similarly, the OP could use his 40a breaker, and use a panel wired with 10awg wire, if he put a 30a fuse or breaker in the panel to protect the wire.

We don't size the wire based upon the "normal" amperage draw of the equipment, we size it to match the breaker (or we fuse the equipment accordingly) so that under catastrophic circumstances the breaker (or fuse) will trip before the wire catches fire.
Click to expand...

Exactly, the breaker protects the wire between the breaker and the outlet, not the appliance plugged into it. A bulb is not a fuse. If the socket, switch, wiring, or any other part of the lamp fails it affects the lamp alone. This could still result in a fire.

Building a panel utilizing a fuse or breaker would be an excellent idea and would almost definitely be required on a commercially sold product, but still this is not to protect the wiring between the breaker and outlet it protects between the outlet and the appliance.

You got the third paragraph right.

Long story short, breakers in the breaker box in your home protect the wire that came in the walls of your home.
 
jeepinjeepin said:
Exactly, the breaker protects the wire between the breaker and the outlet, not the appliance plugged into it. A bulb is not a fuse. If the socket, switch, wiring, or any other part of the lamp fails it affects the lamp alone. This could still result in a fire.

Building a panel utilizing a fuse or breaker would be an excellent idea and would almost definitely be required on a commercially sold product, but still this is not to protect the wiring between the breaker and outlet it protects between the outlet and the appliance.

You got the third paragraph right.

Long story short, breakers in the breaker box in your home protect the wire that came in the walls of your home.
Click to expand...

I am not sure if you are trying to be deliberately snarky here.

To put all this into context, the OP asked if he could use a commercially built control panel wired with 10awg on a circuit protected by his current 40a breaker. He also indicated that he did not have much electrical knowledge.

I replied that it would not be a good idea because the wire is undersized for the breaker. Another poster said it would be no problem because you can always "oversize" the breaker. That is false in the general case, and can have dangerous consequences, so I pointed that out. In the specific case, we are discussing a high voltage brewing control panel.

I would not plug a 240v, 30a rated control panel into a 40a circuit, without additional fuses or breakers to protect the wiring in the control panel. Nor would I do so without a GFCI.
 
jeepinjeepin said:
Exactly, the breaker protects the wire between the breaker and the outlet, not the appliance plugged into it. A bulb is not a fuse. If the socket, switch, wiring, or any other part of the lamp fails it affects the lamp alone. This could still result in a fire.

Building a panel utilizing a fuse or breaker would be an excellent idea and would almost definitely be required on a commercially sold product, but still this is not to protect the wiring between the breaker and outlet it protects between the outlet and the appliance.

You got the third paragraph right.

Long story short, breakers in the breaker box in your home protect the wire that came in the walls of your home.
Click to expand...

Also, a breaker will protect an appliance plugged into an outlet as well, if said appliance has wiring matched to the breaker. If the OP found a 40a rated control panel, his 40a breaker would protect if fine. The more appropriate question is whether an appliance that uses lower rated wiring has proper safety features.
 
I was just trying to break the notion that the breaker (in the panel box) is there to protect the appliance. It does have that added bonus in cases of ranges, hot water heater, air conditioners and such. This control panel would be operating similar to a hot water heater and would benefit from a 30A breaker but it is not required for operation of the unit.

You are absolutely correct in reference to over sizing breakers, with one exception that I can think of (which may no longer be current). Circuits for welders can/could be run with wire suitable to a smaller breaker size due to the short duty cycle of the welder. They also had to be marked and don't apply to this conversation.

I need to look back. It it a 4 wire range outlet and the OP is renting? A 4 wire is required (AFAIK) to run a GFCI on a 240V circuit. If he is renting and cannot make modifications to the home an extension with a 30A GFCI built in would be a good idea.
 
It's a 3 wire range outlet, I believe - I took a quick look for a 30A GFCI extension but am coming up short. Can you point me in the right direction?

Yes, I am renting so can't make any wiring changes or outlet installations.
 
NWMushroom said:
It's a 3 wire range outlet, I believe - I took a quick look for a 30A GFCI extension but am coming up short. Can you point me in the right direction?

Yes, I am renting so can't make any wiring changes or outlet installations.
Click to expand...

Sorry, I don't think GFCI can work with 3 wires on 240v.

It would likely have to be built. I don't think you would find one ready made. It's like building an adapter to fit a square peg into a round hole. It would usually be easier to just get a square hole.
 
There would also be a way to wire a 50 amp GFCI spa panel to both get your GFCI and add a 30a breaker to protect the controller wiring, assuming it does not already include it (and I don't believe the High Gravity ones do). That appears to be the cheapest GFCI option these days.
 
I'm still not sure I agree with the line of thinking here. I will use my electric oven / stove as an example, as I had the unfortunate treat of getting to troubleshoot it over the past few days and replace a faulty controler / timer.

The oven is plugged into a 240v, 3 wire outlet - I don't know the amp rating off the top of my head. The cable into the outlet is substantial, but again, I don't know the rating off the top of my head. Once the cable enters the back of the oven, each lead hits a terminal strip, where numerous other wires come off, all of which are smaller (higher gauge) than the main plug supply. There are no fuses or breakers to protect the myriad of smaller wires, and yet the oven has received the certified approval of various consumer protection and safety listing facilities.

We plug all kinds of electronics into outlets without verifying the wire gauge of the cord as compared to the rating of the breaker. If it was paramount to safety that the cable we plug into the outlet be the same gauge as the breaker would protect for, you can bet we'd have some serious protections in place - there would be different shaped outlets for each amp rating, and plugs would be sold such that the could only plug into an equally rated outlet - that is not the case except with the larger amperage outlets.

I still believe you can plug a 16 gauge lamp cord or a into a 15 amp circuit, even though you'd require 12ga wire in the wall, and have a safe setup. Why would our panels be any different?

(Note - if you CAN match them, why not do it? That's what I did... but I wouldn't cancel the project all together or incur some insane expense to make it happen)
 
jeepinjeepin said:
Sorry, I don't think GFCI can work with 3 wires on 240v.

It would likely have to be built. I don't think you would find one ready made. It's like building an adapter to fit a square peg into a round hole. It would usually be easier to just get a square hole.
Click to expand...

Just use this method:


3-wire-in-4-wire-out.jpg
 
BadNewsBrewery said:
I'm still not sure I agree with the line of thinking here. I will use my electric oven / stove as an example, as I had the unfortunate treat of getting to troubleshoot it over the past few days and replace a faulty controler / timer.

The oven is plugged into a 240v, 3 wire outlet - I don't know the amp rating off the top of my head. The cable into the outlet is substantial, but again, I don't know the rating off the top of my head. Once the cable enters the back of the oven, each lead hits a terminal strip, where numerous other wires come off, all of which are smaller (higher gauge) than the main plug supply. There are no fuses or breakers to protect the myriad of smaller wires, and yet the oven has received the certified approval of various consumer protection and safety listing facilities.

We plug all kinds of electronics into outlets without verifying the wire gauge of the cord as compared to the rating of the breaker. If it was paramount to safety that the cable we plug into the outlet be the same gauge as the breaker would protect for, you can bet we'd have some serious protections in place - there would be different shaped outlets for each amp rating, and plugs would be sold such that the could only plug into an equally rated outlet - that is not the case except with the larger amperage outlets.

I still believe you can plug a 16 gauge lamp cord or a into a 15 amp circuit, even though you'd require 12ga wire in the wall, and have a safe setup. Why would our panels be any different?

(Note - if you CAN match them, why not do it? That's what I did... but I wouldn't cancel the project all together or incur some insane expense to make it happen)
Click to expand...

Yes, my understanding is that stepping down to higher gauge wire in appliances is permitted under certain circumstances, but I am not familiar with the details of the rules. I would expect shorter runs with less resistance to be more "forgiving."

Not really understanding the details, one need not worry about it if sizing wiring based on breaker and fuse ratings. I consider this a prudent appproach, but not necessarily the only safe approach.
 
NWMushroom said:
Are you referring to the length of the cord from the outlet to the controller?
Click to expand...

That, or any other run of wire throughout the entire circuit. To use BadNewsBrewery's example above, he may have a 50a breaker with 6awg to the stove outlet, but there are short runs of wire in the stove itself that are not 6awg. Taking an example in the other direction, if you wanted a really long run from the outlet to the controller, say over 100 feet, you might have to go with a higher rated wire than what we are discussing. Thicker wire means less resistance, longer run means more resistance.

There are formulas and tables to work all this stuff out, but that is well above my pay grade. :) Of course, if you want to do the research and calculate it out, by all means do so. Perhaps you could save some money by downsizing wires, but you may or may not come out ahead, depending upon how you value your time.

Most folks on this forum building panels are not electricians or electrical engineers. The most straightforward approach to safety is to just size the wire based upon your breakers and fuses.
 

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