240V E-biab running on 120V

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Yater

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I am looking at building an E-biab and I am looking at running a new 240v line for the system. I was wondering if I wired the system to run off 240V can i connect it to 120v to run the pump and element to maintain mash temps when not at home. I would boil using propane but this would allow me to bring my brew system to friends houses to brew

I know that 240v elements run at 25% power when plugged into 120v so a 5500 watt element would run at 1375 watts which would be acceptable for any unloaded line.

My thought was get a 120v cord with a built in gfci. I would cut the female end of and wire it with the 240v plug end. Then when I leave my house I would plug the control panel into the 120v gfci cord and plug my system into a 120v outlet. I would have to run the pid and pump off one leg of the 240v system and that leg would be the portion I would keep powered on 120v.

Thoughts and ideas?
 
Yes it possible.
Simplest solution is to to add 25A SPDT switch to connect non controlled by SSR heater's leg either to neutral or hot.
 
I think it's slightly more challenging in that you'll have two power inputs to the panel and there can be safety concerns. You'll need a way to either connect your 240v 4-wire cable OR your 120v 3 wire cable without any male plugs exposed on the panel. Probably the safest way to do it is to make an adapter that goes from a male 20a 120 v to female 4 wire 240v where the appropriate poles are maintained.
 
There are many things we can do at home that we probably shouldnt. I believe this is one of them. I dont want to get code " geeky" but NEC 406.8 prohibits these adapter cords. Most of the time there is sound reason for these codes.
 
I may not have expressed myself very well but I was thinking on making a gfci adaptor. Would you really consider it unsafe thought. The system would be protected by a breaker that would be rated accordingly and I would still be protected by the gfci in the adapter. I don't know the code but you can get welders that can run on both 240v and 120v.
 
I'd suggest making a smaller traveling 110v control box. You can socket your control box with a 220v receptacle that just has 110v legs connected for your element and a plug for your pump.
 
There is technically no danger in making an adapter cord for an appliance you've built to work that way. I'm not saying it's something you want to leave laying around for someone to use on something else. It's certainly nothing like making a male/male cord or anything like that. What you have to be sure about is that your primary power cable to the controller is L1/L2/N/G. Pick one of the hots to be used specifically for your 120v application, for example call it L1. In the controller, you'd wire your PID to L1 and N to get power. You'll wire the pump receptacle and switch on the L1/N/G. L1 is also the line that will go through the SSR to the element.

The only thing L2 will be used for is to come into the control box, go to a double throw switch, then to the element.

See, you'll still need a single pole double throw switch with the second terminal of the element going to the common. The two options on the switch will go to L2 or Neutral.

Your 120v adapter cord will connect L1 to L1, N to N, and G to G. When you plug in your controller to the adapter, it's just going to get L1, N, G and NOT L2. If you have your element switch set to N, it doesn't matter what source you're plugged into but it will only get 120v. If you're adapted to 120v and leave the switch on 240v (L2), nothing will happen because the panel's L2 is not connected to anything at all because of the adapter.

Maybe I'm not seeing the inherent danger in properly doing this. I do know for sure that you can kill yourself if you don't understand what you're doing. Very few people understand 240 volt wiring.
 
Bobby_M said:
There is technically no danger in making an adapter cord for an appliance you've built to work that way. I'm not saying it's something you want to leave laying around for someone to use on something else. It's certainly nothing like making a male/male cord or anything like that. What you have to be sure about is that your primary power cable to the controller is L1/L2/N/G. Pick one of the hots to be used specifically for your 120v application, for example call it L1. In the controller, you'd wire your PID to L1 and N to get power. You'll wire the pump receptacle and switch on the L1/N/G. L1 is also the line that will go through the SSR to the element.

The only thing L2 will be used for is to come into the control box, go to a double throw switch, then to the element.

See, you'll still need a single pole double throw switch with the second terminal of the element going to the common. The two options on the switch will go to L2 or Neutral.

Your 120v adapter cord will connect L1 to L1, N to N, and G to G. When you plug in your controller to the adapter, it's just going to get L1, N, G and NOT L2. If you have your element switch set to N, it doesn't matter what source you're plugged into but it will only get 120v. If you're adapted to 120v and leave the switch on 240v (L2), nothing will happen because the panel's L2 is not connected to anything at all because of the adapter.

Maybe I'm not seeing the inherent danger in properly doing this. I do know for sure that you can kill yourself if you don't understand what you're doing. Very few people understand 240 volt wiring.
Click to expand...

Theres really no inherent danger if your the one wiring and using. I come from the industrial control side of things where you always have to worry about the next guy. Male to male adapters = bodies on the ground. People are killed every year trying to hook up portable generators this way. What you doing should be fine. Just be safe!
 
Male to male was not an option. I always have a female involved. Would the spdt switch be necessary? The L2 would terminate inside the 240v female ends of the adaptor. Would L2 be live because it's connected to the element that is powered by L1?
 
Yater said:
Male to male was not an option. I always have a female involved. Would the spdt switch be necessary? The L2 would terminate inside the 240v female ends of the adaptor. Would L2 be live because it's connected to the element that is powered by L1?
Click to expand...

When you're running true 240v because you have that outlet available at home, the element has to be wired to L1 and L2. When you're running the panel on 120v, you have to redirect the L2 terminal of the element to the panel Neutral otherwise you don't get any voltage at all.

I think what you may have been considering is to connect the panel's L1 and L2 buses to the L1 and Neutral of the 120v system but that wouldn't work because of your desire to control a pump off of the controller. If the controller was only going to be the PID and SSR, you'd be fine doing that because the PID power source can be 120v or 240v, or at least most can. Since you're running a 120v pump, you'll be bringing a neutral into the panel.
 
Thanks for your help.

Bobby in the video you produced testing your RIMS tube, is that all the 120/240 switch does is connect L2 to the L2 or neutral. Where did you get that switch and what ratings am I looking for.
 
It's a Bryant 3025. DPDT 30amp with center off. The center or commons go to the element. The two "throws" switch one side of the element to L1 or L1. The other side of the element switches between L2 and N. The only reason I use a double pole switch is to be able to cut off power completely without using a separate switch or contactor. Another cheaper way to do it is to put a SPST switch rated for 30a on the L1 side of the element (this becomes "element power". Then a SPDT switch on the other side of the element and switch L2/N (call this one Hi/Low power).
 

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