What to do with neutral in 240 volt?

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JVD_X

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For those of you using 240 volts in your system...

The hot element runs from the two hot phases and everything needs to be grounded of course, but what do you do with the neutral that is left from a four-prong plug? Do you simply cap off the wire?
 
For those of you using 240 volts in your system...

The hot element runs from the two hot phases and everything needs to be grounded of course, but what do you do with the neutral that is left from a four-prong plug? Do you simply cap off the wire?
If you have a 4-wire plug then clip the extra wire at the element. Make sure you tape it off. It is a live wire when compared to the 240V wires! You only need 2 wires and the ground for the heating element.
 
You run the neutral back to the neutral bus in the panel.
Having the redundant ground would add additional safety on its own, but on a plug with GFCI in-line, would there be any advantage? (This is assuming that you are not using one of the hot legs to power a 110 device.)
 
I ran my 4 wires to a distribution block, then tapped off that for all of my power needs in the panel. The neutral then was tapped for all the 120VAC components on my rig, the ground and 2 hots used for the element, grounded to the kettle.

Distribution blocks are nice, as they can be your "dead end", but also leave you a place to easily tap 6 loads of that one line.
 
Having the redundant ground would add additional safety on its own, but on a plug with GFCI in-line, would there be any advantage? (This is assuming that you are not using one of the hot legs to power a 110 device.)

It's not a redundant ground. I assume he has a 4 prong plug. 2 wires are the 220V coming into the building, 1 wire is neutral and 1 wire is ground. The neutral is grounded at the distribution box but is not to be used as a redundant ground. Neutral and ground must be kept separated.
 

It's not a redundant ground. I assume he has a 4 prong plug. 2 wires are the 220V coming into the building, 1 wire is neutral and 1 wire is ground. The neutral is grounded at the distribution box but is not to be used as a redundant ground. Neutral and ground must be kept separated.

What he said.
I have been seeing this pop up in a lot of threads lately. READ MORE THREADS BEFORE WORKING WITH ELECTRICITY. Talk to a certified electrician

Never use the nuetral as ground. Electricity will kill you. Trust me you never want to get hit by electricity through the neutral. It hurts real bad. I know from experience.
 
It's not a redundant ground. I assume he has a 4 prong plug. 2 wires are the 220V coming into the building, 1 wire is neutral and 1 wire is ground. The neutral is grounded at the distribution box but is not to be used as a redundant ground. Neutral and ground must be kept separated.
This is where I am confused. I didn't think that a 220V heating element had any use for a neutral wire and that the only time current would be present would be if there was a failure in the system. If this were the case wouldn't the GFCI trip? And because this is a dedicated line to the panel with both wires connected to the same thing on both ends it would be redundant path for current in case of failure.

But as I said in my other post, if you're drawing 110v from one of the legs for another device this does not apply. You don't want to intentionally use your ground wire for a neutral.
 
You are correct. 240v element will not have a nuetral attached. You can put a wire nut on it and tape it up or attach it to a distribution block for later use in a 110v application.

In this situation there will probably never be current running through the neutral. It is pretty safe. Becuase it is a home run to to the panel and it is bonded in the panel theoretically it could be used as redundant ground. NEVER get in the habit of doing this though. Just forget about it. It is not code and in other situations it can cause problems and danger.

As for tripping your GFCI. That is done at the panel. It has a pig tail on the breaker for connecting to nuetral. It will know when there is a over current or undercurrent.

Just think of the neutral as not being there and not needed and cap it.
 
Never use the nuetral as ground. Electricity will kill you. Trust me you never want to get hit by electricity through the neutral. It hurts real bad. I know from experience.
Sorry, I type slow and just read this post.

Am I correct in saying that a heating element doesn't need a nuetral?

Is the OP going to use his 240V cord to run 110V devices?



Edit: Slow again. Question answered!
 
As for tripping your GFCI. That is done at the panel. It has a pig tail on the breaker for connecting to nuetral. It will know when there is a over current or undercurrent.
Not sure of the OP's application, but I was thinking of the wiring for an in-line GFCI like this.

30ampGFI.jpg


If it's going directly to the heating element, does the neutral have any purpose?
 
You are correct. 240v element will not have a nuetral attached. You can put a wire nut on it and tape it up or attach it to a distribution block for later use in a 110v application.

In this situation there will probably never be current running through the neutral. It is pretty safe. Becuase it is a home run to to the panel and it is bonded in the panel theoretically it could be used as redundant ground. NEVER get in the habit of doing this though. Just forget about it. It is not code and in other situations it can cause problems and danger.

As for tripping your GFCI. That is done at the panel. It has a pig tail on the breaker for connecting to nuetral. It will know when there is a over current or undercurrent.

Just think of the neutral as not being there and not needed and cap it.

OK - but that is not the design CodeRage uses on his diagram. He is using the neutral as the return for one leg of the 240 and he uses the ground for the keggles and whatnot.
 
OK - but that is not the design CodeRage uses on his diagram. He is using the neutral as the return for one leg of the 240 and he uses the ground for the keggles and whatnot.

I have to look at his post but I imagine he is doing that as 110v leg for a device that needs 110v. You really should not think of a nuetral as a "return" it will confuse you, and me:D

I will take a look at his post. If you look at Pol's design he is pulling a 110v leg off of his 240v. In order for 110v devices to work, they need a nuetral. This is probably what CodeRage is doing too.
 
Not sure of the OP's application, but I was thinking of the wiring for an in-line GFCI like this.

30ampGFI.jpg


If it's going directly to the heating element, does the neutral have any purpose?


Where are you finding this cord at? I am not familiar with them. I assume it should work just fine. I might want to do that with my system.

The only thing I would consider with this is how far is the Wall plug from the main breaker? I would have to check the code book, but I would assume in a residential setting the distance should not matter much.

I work on the same floor as the code inspectors for the county I work for. I will ask the electrical guy what thinks.
 
OK - but that is not the design CodeRage uses on his diagram. He is using the neutral as the return for one leg of the 240 and he uses the ground for the keggles and whatnot.
If I remember right CodeRage was thinking of running two 110v heating elements. Is this your plan or will you be using one larger 240V?
 
I was only curious.

I already have a 120volt RIMS/Propone design outside... works very well but I am building a smaller 5 gallon pilot system for my basement.

I can't make up my mind if I want to have the basement bar/brewery plumped for natural gas (direct heat mash) or use all electric in a RIMS or HERMS. I already have natural gas in the basement for my hot water heater. Each choice has it's pros/cons.
 
With a 240V water heating element it won't have a neutral and ground. When used in a water heater the metal core of the water heater is grounded. A 240V circuit doesn't use a neutral in the loop like 120V does. A 240V appliance like an oven will use a four prong plug so that it can split 120V off one leg of the 240V to power features like clocks and the oven light. It then uses the neutral to complete that 120V circuit.

If you're building a 240V panel to run your system off of a 4 prong plug, you should build out the two 120V legs, the neutral and the separate ground. It might not be *needed* but would give you the most flexibility if you want to split 120V off for pumps, lights, displays, etc...
 
If you're building a 240V panel to run your system off of a 4 prong plug, you should build out the two 120V legs, the neutral and the separate ground. It might not be *needed* but would give you the most flexibility if you want to split 120V off for pumps, lights, displays, etc...
Instead of cyberbackpacker's 4 wire, I picked up a 3 wire GFCI cord for my electirc HLT, but there's nothing running off it but the heater. Came into this thread to make sure there weren't any saftey issues. Thanks to all for the info and sorry for any hi-jack.

Electric03.jpg

Electric HLT w/ 3000W 240V Ogden Thermostat Immersion Heater
 
As has been said, a heating element only needs the two hots. Don't just hook up the neutral to something because it's there. If anything it'll cause false GFCI trips and dangerous electrical hazards. Only use the hots and ground. Your clothes dryer probably uses neutral for the light, and your oven for the light and clock.

But I run 4-wire plugs to everything anyway. I would hate to one day decide I need the neutral, and not have it available. To run a pump or something.

Bottom line - HOTs and NEUTRAL carry current under normal conditions. GROUND only carries current to save your butt if there's a problem! And then the GFCI detects this problem and shuts stuff off.
 
Nice website (ohiobrewing)

since we're talking volt brewing, does anyone sell a keggle which has been converted for electric ? I do not want to do the conversion myself. I can use as HLT and boil kettle, but would need to regulate (easy with propane)
 
In the primer OP drawing, L1 and L2 are being switched by an SSR and go straight to the element. there is a neutral that crosses underneath it running the pump which is 110V, maybe you got the lines confused?

I prefer to use ladder type drawings which makes those kinds of things a little clearer but it can be confusing to people who haven't been exposed to it. So I used a quasi mechanical wiring diagram. I'll see what I can do to make it clearer.

OBT has it right on the money.
 
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