240V with no neutral? Can I build a rig?

CornyKegs 728
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Are they available for an odd outlet like that 240 as well? That's the source of my concern and confusion, I was under the impresion that gfi used the neutral.
 
magnj said:
Are they available for an odd outlet like that 240 as well? That's the source of my concern and confusion, I was under the impresion that gfi used the neutral.
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I've only ever seen 240v GFCI's as a breaker or as a cord. The cords I've only ever seen in 30A models.
 
magnj said:
Are they available for an odd outlet like that 240 as well? That's the source of my concern and confusion, I was under the impresion that gfi used the neutral.
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For the 240 volts, I think your cheapest solutions is going to be a 50 amp spa disconnect panel from Home Depot (about $50). See post #7 above for how I wired mine to my 3-prong 30 amp dryer outlet (this is for 240 volts only, without a neutral output). I use a separate 120 volt outlet for my pump with a cheap 120 volt, 15 amp GFCI - I think I paid about $10 or $12 for it.

EDIT: more info about GFCI's here:

http://www.codecheck.com/cc/gfci_principal.htm
 
I believe DeafSmith has said it but just to clarify a 240VAC GFCI does NOT need a neutral. It actually "watches" the current on both hots and trips when there is a difference. Which is different from a 120VAC GFCI which "watches" the hot and neutral.

Also, the Spa Disconnect panel is the way to go if you ask me. You dont need to worry about bus bars and mounting a breaker(s) as they are all in the panel. It comes with a 50A GFCI breaker installed and you can buy the same style breaker but 15A and 120VAC and snap it in to take care of your pumps.

EDIT: Sorry...since the 120VAC is coming from another source how is the breaker going to be powered since it snaps into the same bus as the 240VAC 2-pole breaker...? If you use this method then the 120VAC breaker is powered off one of the legs of the 240. Deaf, where id your 15A GFCI...in your main panel feeding the rig?
 
SOB said:
EDIT: Sorry...since the 120VAC is coming from another source how is the breaker going to be powered since it snaps into the same bus as the 240VAC 2-pole breaker...? If you use this method then the 120VAC breaker is powered off one of the legs of the 240. Deaf, where id your 15A GFCI...in your main panel feeding the rig?
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I'm using the spa box only for 240 volts from my dryer outlet to power my stove. The 120 volts for my pump is from a standard 120 volt wall outlet. The 120 volt GFCI plugs into the wall outlet and a regular 120 volt outdoor extension cord plugs into that GFCI. So I really don't have a main panel on my brew rig, just a manually controlled electric stove (rebuilt drop in rangetop) powered with 240 volts, and a single March pump on 120 volts. All manual, no automation.
 
So I'd be looking at:
240V @ Wall -> Spa Panel w/50a gfci -> Rig control box <-120V extension cord <-120v gfci @ wall

2 separate power sources to the control box. The 240V powering the elements, the 120V powering the pumps?
 
I'd mount the 120v GFCI in the control box just for kicks, unless you already have one mounted where you're brewing.
 
Ok, any particular reason? I thought it was more of a plug in type thing?
Any suggestions on spa panels?
 
I would not run two sources into the same control panel.
If you have to use a separate source for the 120v pumps, I'd have a searate box to run them.

Besides all the opportunities to intermix the sources inside a single box, I think of my brew days... and by the end of cleanup, there has usually been some consumption. I can see a helper / visitor / friend looking down seeing a cord laying on the floor and thinking the box is not energized.

I have no idea how far this outlet is from the main panel on the property, but I think P-J was about to suggest running a separate ground for the outlet and using the current ground wire as a neutral wire. I think that would be a great option if the conditions are right.

Ed
 
magnj said:
Ok, any particular reason? I thought it was more of a plug in type thing?
Any suggestions on spa panels?
Click to expand...

Here's the spa panel:
http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053

You can use it with a 3 prong outlet for 240 only as previously described, or with a 4 prong outlet with a neutral for 240 and 120. So probably the cleanest way is to add another wire to your outlet so you'll have a neutral, otherwise just use a separate 120 volt outlet for your pump. Ohio-Ed did bring up a valid concern about mixing the voltages in one box. In my case, I bring the 240 into a fused disconnect box:

http://www.lowes.com/pd_12587-1318-LF211NU_0__?productId=1008293&Ntt=disconnect+switch&pl=1&currentURL=%2Fpl__0__s%3FNtt%3Ddisconnect%2Bswitch

and from there to my stove.

The 120 goes into a separate box on which I have mounted a dual 120 v outlet and a toggle switch. The switch controls one of the outlets, for my pump; and the other, which is not controlled by the switch, I use for a fan to keep the bottom of the stove cool.
 
I guess I could build 2 separate boxes...But this is getting more complicated and more hacky than I had hoped :(
 
I wouldnt consider it "hacky" at all and it's much easier than trying to run a neutral conductor to an existing outlet.
 
magnj said:
I guess I could build 2 separate boxes...But this is getting more complicated and more hacky than I had hoped :(
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Keep in mind we are just throwing out options since we really don't know what you've got over there. Everything is just speculation until you pop the cover off of that outlet. My 50A 3prong receptacle in the garage just happened to have a Neutral and a Ground run to it, you may just get lucky!
 
That's true. And trust me I appreciate the help! I'm headed over there tom after work. Worst case scenario I can always build system with a single 120v rims to maintain temps. We'll figure it out :)
 
Ohio-Ed said:
...
I have no idea how far this outlet is from the main panel on the property, but I think P-J was about to suggest running a separate ground for the outlet and using the current ground wire as a neutral wire. I think that would be a great option if the conditions are right.
Click to expand...
Ed,

That is exactly where I was going. With most older 240V systems (i.e. A 50A outlet for a stove) the power was deliveres in a 3 wire cable. The wires are Phase A (120V), Phase B (120V) and Neutral. The equipment ground is not delivered. Neutral and equipment ground were considered to be the same and is within NEC code from that time. The code was changed to address safety issues that surfaced later on. With todays NEC code neutral and ground are delivered using seperate conductors.

It would be a very simple solution to run a Ground conductor to the outlet box. It does not have to be run in the same path as the power cable.

Until magnj actually looks at his setup and determines what he has, it is really just speculation. We will have to wait and see.
 
magnj, Always make any checks with the circuit breaker off. If you're going to make a sub-panel (using a spa panel 50A GFCI), then there are a few things that need to be considered. All conductors (including ground) must be in the same cable or conduit (NEC 250.32 (B), 300.3 (B)). The best way is to check with the local Bldg. Dept. or electrical inspector, because codes differ from town to town. Therefore, you'd have to run a four wire cable from the panel. If you want to change the existing 6 AWG setup to 120 VAC, you can re-identify one of the insulated conductors as neutral by using white electrical tape. The grounds and neutrals must be separated in the sub-panel. All neutrals on the N bus, and all grounds on the ground bus. The neutral bus must not be connected to the panel enclosure (bonded). If the spa panel you purchase does not come with separate ground and neutral buses you can purchase one. HD/Lowes sells bus bars that are made for a Siemans, Square D, Murray, etc. panels.
“To check the gauge of the wire, I turn off the circuit breaker then pull it out?”
Normally the wire gauge is printed on the insulation of the wire (both outer and inner). 6/3 Romex (or NMB) will have 6/3 printed on the outer jacket, then something like, 600 Volts 6 AWG, on the individual conductors. On older conductors (30+ years old, this may not be the case.) If there is no printing and you have enough slack in the panel or outlet box, you can cut a small (1”-2”) piece and bring it to HD/Lowes and ask the electric dept. guys to tell you. No need to remove the breaker, the amperage should be printed on the handle.
 
SOB said:
I believe DeafSmith has said it but just to clarify a 240VAC GFCI does NOT need a neutral. It actually "watches" the current on both hots and trips when there is a difference. Which is different from a 120VAC GFCI which "watches" the hot and neutral.
Click to expand...

I disagree with this. The GFCI breaker I just wired in 2 weeks ago I messed up on. I ran both hots from the outlet to the appropriate screws on the breaker. Not thinking about it being GFCI, I ran the neutral wire from the outlet to the neutral bus instead of to the GFCI breaker. Anytime I put any load on the circuit, the GFCI would trip. The whole reason GFCI breakers have the pigtail is to complete the neutral path after wiring the outlet to the neutral screw on the GFCI breaker. This experience would contradict your statement that it merely watches both hots. This was a GFCI from the HD Spa Panel. There are 3 screw positions on the GFCI breaker, 2 for hots and one for neutral.
 
bbognerks said:
I disagree with this. The GFCI breaker I just wired in 2 weeks ago I messed up on. I ran both hots from the outlet to the appropriate screws on the breaker. Not thinking about it being GFCI, I ran the neutral wire from the outlet to the neutral bus instead of to the GFCI breaker. Anytime I put any load on the circuit, the GFCI would trip. The whole reason GFCI breakers have the pigtail is to complete the neutral path after wiring the outlet to the neutral screw on the GFCI breaker. This experience would contradict your statement that it merely watches both hots. This was a GFCI from the HD Spa Panel. There are 3 screw positions on the GFCI breaker, 2 for hots and one for neutral.
Click to expand...

Methinks you need to research a bit more on how a GFCI works...

Walker has summed it up nicely here...

Walker said:
I can't stay away from this thread. The link posted very early (how GFCI works) has all the goods in it.

I'd like to try and summarize the clever science involved in a way that is not terribly difficult to follow, because when I read about it to gain my own understanding I found it very elegant and simple. Pure genius, really.

The key to the whole thing is a small coiling piece of metal, formed into a ring like a donut. If you take a device like this and run a wire through the center of the donut, you have the beginnings of a GFCI device. When current travels along that line through the hole, electro-magnetic forces are created around the wire. These forces cause current to start to flow through that coil, even though the donut and the current carrying wire are not actually physically in contact with each other.

When current is flowing one way (say left-to-right) in the wire, the current in the coil flows one way (say counterclockwise around the donut). When current on the wire in the hole moves the other way (right-to-left) the donut carries current in the clockwise direction.

When there is no net current moving on the line int he center of the donut, the donut coil itself carries no current.

So.... to make a GFCI detector....

All lines that are permitted to carry current in the circuit (be they hot lines or neutral lines) are passed through the doughnut hole together. The coil will monitor ALL of them simultaneously. If there is a net current flowing left-to-right, the coil carries counter-clockwise current. If there is a net flow of current from right-to-left, the coil carries clockwise current. If there is no net flow of current, the coil carries no current.

All that needs to be done then is to have circuitry that monitors the current IN THE DONUT COIL itself. If there is ever current moving around the donut in either the clockwise or counterclockwise direction at all, then that means that net current of the total group of lines passing through the center of the donut is not balanced and some current has found an alternate way of getting out of the system.

It does not matter if you are monitoring 1 hot and 1 neutral, 2 hots alone, 2 hots and a neutral, or even 101 hots and 37 neutrals.... it is totally irrelevant. All that matters is that all of these lines are passing through the hole of the magic donut coil and that the amount of current that is flowing left-to-right in some of the wires in the group is also flowing right-to-left in other wires in that group.
Click to expand...
 
A GFCI breaker works by monitoring the difference in current between hot and neutral, regardless if it's 240v or 120v.
http://www.ehow.com/how-does_4898026_gfci-circuit-breaker-work.html

That is how it works. GFCI breakers have pigtails for a reason. They will not work without connecting the neutral from the receptacle to the breaker.

GFCI CORDS are different. I have no say on that. But GFCI BREAKERS must have the neutral connect to work. I was merely disputing the statement that he said it monitors both hots to check for current differences.
 
bbognerks said:
A GFCI breaker works by monitoring the difference in current between hot and neutral, regardless if it's 240v or 120v.
http://www.ehow.com/how-does_4898026_gfci-circuit-breaker-work.html

That is how it works. GFCI breakers have pigtails for a reason. They will not work without connecting the neutral from the receptacle to the breaker.

GFCI CORDS are different. I have no say on that. But GFCI BREAKERS must have the neutral connect to work. I was merely disputing the statement that he said it monitors both hots to check for current differences.
Click to expand...

I don't see where SOB said anything about a GFCI Breaker where you quoted him, he simply said GFCI.

This is my understanding of how things work. Yes a 240V GFCI Breaker has a neutral pigtail and yes you need to wire that up to make a 240V GFCI Breaker work, but it does not use that neutral line to trip the GFCI. Fundamentally 240V power works differently than 120V. 240V uses 2X 120V "hot" lines to provide power, a GFCI in that instance monitors those lines for any imbalance and trips if an inbalance is found. 120V uses a 120v "hot" and a neutral, a GFCI in this instance will monitor the hot and neutral for any imbalance.

Someone with more electrical knowledge than myself may chime in and tell me to stop pushing propaganda, but this is my understanding of how this works.
 
Ah after reading that thread, I see where you wouldn't need a neutral. They make 2 pole GFCI breakers that don't have a neutral input and they just monitor the hots. But with this type, you can't break off into a separate 120v leg inside your control panel. I stand corrected somewhat, but for the breaker in the HD spa panel, you still must have the neutral for it to work.
 
bbognerks said:
Ah after reading that thread, I see where you wouldn't need a neutral. They make 2 pole GFCI breakers that don't have a neutral input and they just monitor the hots. But with this type, you can't break off into a separate 120v leg inside your control panel. I stand corrected somewhat, but for the breaker in the HD spa panel, you still must have the neutral for it to work.
Click to expand...

Correct! You need to have that neutral on the line side for that GFCI breaker to work.
 
There I go again, making an ass out of myself by assuming he meant the GFCI breaker included with the HD Spa panel. Sorry for any confusion. I just wanted to share my experience with wiring in the spa panel breaker. It had me scratching my head for a bit trying to figure out why it was still tripping when all my wiring looked good inside my control panel.
 
P-J, I was talking about him running a spa/sub panel. 250.130 (C) is for receptacles. If he wanted to add a ground to his 120 or 240 circuit, that would be okay. Most of the older type 240 VAC circuits I've run into (here in NY) have been using SE type cable. Two hots and an uninsulated wire that acted as the neutral. That's because the loads balanced out and there was no current on the neutral. You can't just decide to use an uninsulated conductor to start carrying current. It's hard to debate this point when we don't know what type of wiring we're talking about. I’m only familiar with what I’ve seen here. I did however, recently see a dryer run off of 10/2 SJ (?) cord. Black and green as the current carrying conductors and white tied to the neutral/ground bus (probably not a licensed job...). If that wire had been black, white and red I could’ve fixed it easily, but I had to run a new 10/3. (okay I’m starting to drift toward ECN/Mike Holt territory here…) I know that there’s also an exception if the building is detached or not, but I’m suffering from midnight shift dementia right now. What do you do in NC? pete
 
You guys have been busy since I last checked in! Unfortunately I did not make it to my friend's house, blizzard. But when I do I'm going to turn the circuit off and check out the wire, we can go from there I guess. How do I know if the third wire is being used as neutral or ground?
 
magnj said:
How do I know if the third wire is being used as neutral or ground?
Click to expand...

If there are only 3 wires then it's being used for a ground. If it's uninsulated it should only be used as a ground, if it's insulated you can use it as a neutral and run another ground. If there are 4 wires then the White one is a neutral & the bare one or green one is a ground.
 
Thanks for all the help guys. However because of my lack of electrical knowledge and the costs, I think I'm going to end up going with a 120V setup to just maintain mash temps and use propane to do major heating and boiling.
 
Hang around here a little longer, you'll get the hang of this stuff in no time. In the meantime there is certainly nothing wrong with propane.
 
magnj said:
Thanks for all the help guys. However because of my lack of electrical knowledge and the costs, I think I'm going to end up going with a 120V setup to just maintain mash temps and use propane to do major heating and boiling.
Click to expand...

I think that is a great plan and one you can make very portable.
You can run a 1500watt rims heater AND a march pump on a 15amp outlet... you can always find a place to plug it in.

Ed
 
Thanks, it's not even so much that I couldn't figure it out as I don't want to half ass it. I don't own my own space, but I think I will be able to get a 20 amp gfci 120V breaker in my box and run an extension cord to where I brew, should be enough to maintain mash temps.
 
Thats true, how many watts do you think I need to maintain mash temps in an aluminum kettle outdoors in the winter? I know I could use a cooler but they are already purchased.
 
magnj, Instead of using a 20A GFCI breaker, you could use a standard 20A breaker, then put a 1900 box and a 20A GFCI and duplex receptacle (4 outlets all together) at the end of a 20A extension cord. The GFCI, outlet, 1900 box and cover will cost you less than a 20A GFCI breaker and still provide you with GFCI protection. Plus it can be easier to wire, especially if the panel is kinda full.
 
I will take that into consideration, thanks. I actually just ordered a 1500W element so I'll probably do this all on 15a and just use a plug and play GFCI at the outlet for even more flexibility.

Now I'm trying to figure out what I need/want out of the control box. Basically just the element and the pump, maybe an emergency stop and an on/off override for the pid?
 
magnj, This is where my knowledge ends. I'm a electrician (mostly residential) who's becoming a brewer, not the other way around. My experience with electric brewing stops at my stove...
 
I only read the last two pages, so forgive me if I miss something beforehand.

You can use a 240GFCI breaker, even one that has a neutral pigtail, on a 240V service that does not have a neutral.

However, you can not use the neutral on the GFCI. It will be strictly a 240V circuit, and you will still have GFCI protection.

You could use this circuit to power your heating elements then run a secondary 110VAC circuit for your controls (PID, Brewtroller, BCS, relays, what have you).
This is what I did with my brewery at first when I was using the dryer's 240V service which had no neutral.

The important thing to remember is to not mix the line and neutral from the 110 circuit with the 2 lines from the 240V circuit. For example never use the neutral with one of the lines from the 240V to get 110.

I see your renting, so you could pull power from your range(is it electric?) or dryer with the appropriate cable, tied that into the supply side of a spa breaker and then use the load side of the spa breaker to provide power to your elements.

Then an extension cable plugged into an outlet will give you your 110. If it isnt a gfci outlet you could put a gfci outlet in a single gang box, wire the supply side to the extension cord and the supply side to your controls and you'll be good.
 
Thanks CodeRage, but I decided to go 120V RIMS and propane burners for now. I think it will be cheaper, portable, and less likely that I F* something up.
 
Code rage,
I'm am currently setting up a system similar to what you used with a separate 110v and 240v. I'm using a HD spa panel with GFCI. The breaker has a neutral pig tail which I understand I do not need in order to be gfi protected. The question is what to do with the pig tail and the ground from my rig. Do I just secure the pig tail to the neutral bus which goes no where. Then secure the incoming neutral (used as ground) and the ground from my kettle to the ground bar in the spa panel? I think this is correct. Anyone chime in please.
 

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