Brewing with 240V

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HopHead0814

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Greetings! I have a 10 Gallon Anvil Foundry and want to switch to using 240V. I just ran 100 feet of 8/3 Romex to my garage, added a 40 amp breaker to my panel, and installed a 30 amp 14-30 dryer receptacle. My thought was it could potentially be used for an EV down the road. I don’t want to cut the cord on my Foundry and it was before they started shipping them as 240V. I want to brew safely and have seen some videos online on how to create a gfci protected inline power cord, but the components are hard to find and/or don’t match my setup. Any advice on what I would need to make a power cord considering what I have would be greatly appreciated. I’m certainly no electrician and am new to brewing. Thanks!
 
You have a 30 amp rated receptacle on a 40 amp breaker.
This is no bueno. Your receptacle can smolder and burn before the breaker trips. Breaker should have lower rated amperage than everything downstream it’s connected to for safety.

Also- at 30/40 amps it might be cheaper to put in gfci breaker vs trying to rig up an inline gfci.
 
This is no bueno. Your receptacle can smolder and burn before the breaker trips. Breaker should have lower rated amperage than everything downstream it’s connected to for safety.

Also- at 30/40 amps it might be cheaper to put in gfci breaker vs trying to rig up an inline gfci.
Thank you for the information. I appreciate it. If it were your house, how would you change it? Change the receptacle to 50 amp? Change the breaker to GFCI 30 amp? Rip it out the receptacle and breaker and put something else in? As I said, I’m not an electrician and the last thing I would want to do is put a fire hazard in my home.
 
There's nothing wrong putting a low rated receptacle on a higher rated breaker. The breaker is sized to protect the wire. 8/3 romex can handle 40 amps.

What some are suggesting as less than ideal is using a device with a normal operating amperage of about 14 on a circuit capable of 40amps. The idea is that if that 14 amp appliance malfunctions and draws 30 amps, the breaker won't trip to protect the smaller wires and circuits plugged into that outlet.
The odds of a device like the Foundry having a fault that draws above rated current but isn't a dead short would be rare.
We usually don't worry about that situation anywhere else. We plug a 1.5 amp phone charger into a 15 amp circuit all day.

If you were one to worry about a very rare chance of bad things happening, you could just swap in a 20 amp breaker temporarily and you might as well make it a GFCI type. You can always swap back to a 40 if you do get an EV.
 
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There's nothing wrong putting a low rated receptacle on a higher rated breaker. The breaker is sized to protect the wire. 8/3 romex can handle 40 amps.

The breaker protects the entire circuit, and depends on any receptacle to handle the max rated load. Undersizing anything is bad juju and unlikely to meet code anywhere. Either upgrade the outlet or downgrade the breaker.

And plugging a low amp device on a higher amp circuit really has nothing to do with the max load behavior...

Cheers!
 
The breaker protects the entire circuit, and depends on any receptacle to handle the max rated load. Undersizing anything is bad juju and unlikely to meet code anywhere. Either upgrade the outlet or downgrade the breaker.

And plugging a low amp device on a higher amp circuit really has nothing to do with the max load behavior...

Cheers!
Thanks for the explanation. I appreciate it!
 
There's nothing wrong putting a low rated receptacle on a higher rated breaker. The breaker is sized to protect the wire. 8/3 romex can handle 40 amps.

What some are suggesting as less than ideal is using a device with a normal operating amperage of about 14 on a circuit capable of 40amps. The idea is that if that 14 amp appliance malfunctions and draws 30 amps, the breaker won't trip to protect the smaller wires and circuits plugged into that outlet.
The odds of a device like the Foundry having a fault that draws above rated current but isn't a dead short would be rare.
We usually don't worry about that situation anywhere else. We plug a 1.5 amp phone charger into a 15 amp circuit all day.

If you were one to worry about a very rare chance of bad things happening, you could just swap in a 20 amp breaker temporarily and you might as well make it a GFCI type. You can always swap back to a 40 if you do get an EV.
I appreciate you taking the time to answer. This really helped me understand where some people were coming from.
 
A 30amp gfci breaker is the way to go. For the cord here is a good way to make an adapter so you don't have to cut the stock cord.

So if I swapped in a 20 or 30 amp GFCI breaker, I could use these same items, except I would need a 14-30 plug adapter instead? Is 12/2 good enough?
 
Undersizing anything is bad juju and unlikely to meet code anywhere.
This might be a bit of an overstatement. Most homes have 20 amp branch circuits with multiple 15 amp receptacles, and that meets code everywhere. But I don't know why anyone would ever undersize the receptacle on a dedicated single outlet circuit. Wire it for the device you want to use it for.
 
Theoretically (maybe even legally?) a device that requires a 20A 120VAC supply would use a NEMA compliant plug for same, such that those 15A sockets would never see a 20A load...

Cheers!
 
Theoretically (maybe even legally?) a device that requires a 20A 120VAC supply would use a NEMA compliant plug for same, such that those 15A socket would never see a 20A load...
Yes. Legally. I actually had typed that but deleted it since I didn't really think this was the place to start reciting the NEC. But since you mentioned it, wouldn't a 40 amp device also have to have a NEMA compliant 40 amp plug that would not fit into a 30 amp receptacle?
 
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I would think that would be the case - right up until laymen are wiring pigtails and outlets :)

Cheers!
For the record, the outlet was installed by a friend who spent 15 years as an electrician before switching to the low voltage side. I posted on here because I know there are great people on here much more knowledgeable than I am on the subject and was only trying to educate myself.
 
There's nothing wrong putting a low rated receptacle on a higher rated breaker. The breaker is sized to protect the wire. 8/3 romex can handle 40 amps.

Actually, there is. By code, single-receptacle circuits must have the receptacle sized to the capacity of the circuit they are on. 30 amp outlet means you must have a 30 amp breaker (and appropriate wiring). Nothing wrong with 8/3 romex here since it's over the rating, but you can't use a single 30 amp outlet on a 40 amp circuit.

This might be a bit of an overstatement. Most homes have 20 amp branch circuits with multiple 15 amp receptacles, and that meets code everywhere. But I don't know why anyone would ever undersize the receptacle on a dedicated single outlet circuit. Wire it for the device you want to use it for.

That meets code because it's a multi-receptacle branch circuit, and those 15 amp receptacles are rated for 20 amp pass-through.

Bottom line is that undersizing the receptacle on a single outlet circuit violates code.
 
No. This adapter gives you 4X 15/20A @ 120V from a 30A @ 240V outlet. It won't let you run your AOI at 240V.

Brew on :mug:
Thank you. So ultimately I'll have to make an adapter? Or as some have implied, have a licensed electrician make an adapter for me?
 
Thank you. So ultimately I'll have to make an adapter? Or as some have implied, have a licensed electrician make an adapter for me?
The straight forward adapter, a pigtail with a 14-30 plug on one end and a 5-15, or 5-20 receptacle (outlet) on the other end, would be a potentially dangerous piece of gear. It would allow you to plug 120V rated appliances into a 240V branch circuit, which will lead to electrical overload, probable appliance failure, and maybe a fire. I suspect such an adapter cord would be a code violation.

A better option would be to replace the plug on the Anvil cord with the proper 240V plug (a NEMA 14-30 in your case), and make a pigtail with a 5-15 or 5-20 plug on one end and a 14-30 receptacle on the other end. This would give you the option to revert back to 120V operation with your Anvil. This adapter cord doesn't have the danger potential of the one in the previous paragraph, as it only allows plugging a 240V appliance into a 120V outlet. The appliance won't work properly (unless it's dual voltage capable), but it's unlikely to damage the appliance, and you won't have an electrical overload potential.

Brew on :mug:
 
The straight forward adapter, a pigtail with a 14-30 plug on one end and a 5-15, or 5-20 receptacle (outlet) on the other end, would be a potentially dangerous piece of gear. It would allow you to plug 120V rated appliances into a 240V branch circuit, which will lead to electrical overload, probable appliance failure, and maybe a fire. I suspect such an adapter cord would be a code violation.

A better option would be to replace the plug on the Anvil cord with the proper 240V plug (a NEMA 14-30 in your case), and make a pigtail with a 5-15 or 5-20 plug on one end and a 14-30 receptacle on the other end. This would give you the option to revert back to 120V operation with your Anvil. This adapter cord doesn't have the danger potential of the one in the previous paragraph, as it only allows plugging a 240V appliance into a 120V outlet. The appliance won't work properly (unless it's dual voltage capable), but it's unlikely to damage the appliance, and you won't have an electrical overload potential.

Brew on :mug:
This makes so much more sense. Thank you for sharing. It'll get me up and running on 240V and if I ever move later down the road (unlikely), I can make the pigtail you suggested to still be able to brew on 120V. I appreciate you.
 
A 30amp gfci breaker is the way to go. For the cord here is a good way to make an adapter so you don't have to cut the stock cord.

I would recommend not making the adapter in this video for the reasons I stated in the first paragraph of this post.

Brew on :mug:
 
Actually, there is. By code, single-receptacle circuits must have the receptacle sized to the capacity of the circuit they are on. 30 amp outlet means you must have a 30 amp breaker (and appropriate wiring). Nothing wrong with 8/3 romex here since it's over the rating, but you can't use a single 30 amp outlet on a 40 amp circuit.



That meets code because it's a multi-receptacle branch circuit, and those 15 amp receptacles are rated for 20 amp pass-through.

Bottom line is that undersizing the receptacle on a single outlet circuit violates code.
I believe you. I wonder what dangerous situation the OP's arrangement has that would magically disappear if the device was a 30 amp welder.
 
A 30 amp outlet on a 40 amp circuit is still against code even if a welder is plugged in. Probably nothing will happen, I'm just pointing out that it is against code. To each their own.

Either way, a standard 30 amp 2 pole breaker is pretty inexpensive, and if OP is buying a GFCI breaker (which they should), then they're buying a new breaker anyhow.
 
1. Others are correct that 30A receptacle and downstream 30A flexible cord will be a code violation. Not the most dangerous thing ever, but not great. (Why not just run #10s if we're throwing caution to the wind? {Don't actually do that.})

2. If the heating element is nominal 120V and you attach it to 240V, you will quadruple the power output. All kinds of issues if not designed for this.

3. I would not take for granted that the 120V appliance has the requisite switches, relays, and wiring, unless mfr confirms. Most 120V gear would not switch the neutral, meaning at 240V it will be energized 24/7.
 
2. If the heating element is nominal 120V and you attach it to 240V, you will quadruple the power output. All kinds of issues if not designed for this.

3. I would not take for granted that the 120V appliance has the requisite switches, relays, and wiring, unless mfr confirms. Most 120V gear would not switch the neutral, meaning at 240V it will be energized 24/7.
The 10 gallon Anvil Foundry is designed to run on either 120 or 240 V. It has a switch for selecting the voltage, which also changes how the element is connected such that power is not quadrupled. Don't have a schematic for the wiring, so don't know if it switches what is the neutral wire for 120V.

Brew on :mug:
 
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