Dual v 120/240 (2 pole?) GFCI?

FlyFishn

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Does it exist?

I'm thinking about making a portable power solution that will allow both voltages like a NMEA 14-30L plug. There are lots of in-line options for either voltage, but I haven't come across something that protects both circuits.

There are generator power hubs that are fed with a dual voltage supply and split to either at the hub that have GFCI. That is along the lines of what I'm thinking - but I want to protect at the source, not the distribution panel.

Here's an example of a power hub with GFCI:
 
Does it exist?

I'm thinking about making a portable power solution that will allow both voltages like a NMEA 14-30L plug. There are lots of in-line options for either voltage, but I haven't come across something that protects both circuits.

There are generator power hubs that are fed with a dual voltage supply and split to either at the hub that have GFCI. That is along the lines of what I'm thinking - but I want to protect at the source, not the distribution panel.

Here's an example of a power hub with GFCI:
All the major suppliers for electrical distribution panels mak 2 pol GFIC breakers in a variety of amperages.
 
What's the application?

Depending on what you're doing you may not even want GFCI protection. Unless you're providing power near water or have other grounding hazards the normal circuit breaker at the mains may be plenty.

Of course consult with applicable codes and safety regulations but it might be better to let someone else (like the supplier listed above) take liability if doing anything remotely hazardous.

John
 
The application is quite wide. I have been systematically building my backup/portable power over the past few years. Right now all I can supply is 110v, however I want to expand that to both 120/240v - which runs on 4 conductors (L1, L2, Neutral, and Ground). I have an L14-30 plug on a cable for my open frame generator. However, it's wired for 2x 110v circuits (L1-N, L2-N), and doesn't carry 220v (which requires L1-L2 - they don't come together anywhere). I set it up that way at the time to allow balancing each leg of the generator - as opposed to trying to run everything off of one 110v plug/chord (would pull from one leg or the other, unbalanced).

I want to keep the same theory of the 4 pin 120/240v connectors and cable with a main supply line of 100ft (may split to 2x 50ft or 25ft and 75ft). The line would be multi-purpose for getting higher current (and both voltages) power anywhere - like welding in garages where the only 220v power that is accessible is a dryer plug somewhere (NMEA 14-30, not an L14-30).

Here is an example of an in-line GFCI breaker:
That one is 30a 220v - but only has 220v (L1, L2, Ground). If there is one like that which has L1, L2, Neutral, and Ground (4 pins, not 3) that is what I'm after. Then its as modular as the cable set up - if I am set up off a generator I can plug it in at the generator and everything down-stream is protected. Ideally, if I am running power outside (off mains, not generator) it would be nice to have the added protection.

For an example - I used to be on a search/rescue team and we had a trailer that was used as a command center with an office. It was run off of generator power. I can't remember what I was hooking up, could have been a radio antenna cable or another AC line. I was kneeling down where our pass-through compartment was to run the line and as soon as I touched the trailer I got hit with 110v. Somehow I ended up completing the circuit to ground. I'd rather not replicate that experience. In this example the generator and the trailer both should be grounded (and were - that particular time the trailer was not - but therein is the point - a GFCI would have tripped and I wouldn't have got the shock I did).
 
The application is quite wide. I have been systematically building my backup/portable power over the past few years. Right now all I can supply is 110v, however I want to expand that to both 120/240v - which runs on 4 conductors (L1, L2, Neutral, and Ground). I have an L14-30 plug on a cable for my open frame generator. However, it's wired for 2x 110v circuits (L1-N, L2-N), and doesn't carry 220v (which requires L1-L2 - they don't come together anywhere). I set it up that way at the time to allow balancing each leg of the generator - as opposed to trying to run everything off of one 110v plug/chord (would pull from one leg or the other, unbalanced).

I want to keep the same theory of the 4 pin 120/240v connectors and cable with a main supply line of 100ft (may split to 2x 50ft or 25ft and 75ft). The line would be multi-purpose for getting higher current (and both voltages) power anywhere - like welding in garages where the only 220v power that is accessible is a dryer plug somewhere (NMEA 14-30, not an L14-30).

Here is an example of an in-line GFCI breaker:
That one is 30a 220v - but only has 220v (L1, L2, Ground). If there is one like that which has L1, L2, Neutral, and Ground (4 pins, not 3) that is what I'm after. Then its as modular as the cable set up - if I am set up off a generator I can plug it in at the generator and everything down-stream is protected. Ideally, if I am running power outside (off mains, not generator) it would be nice to have the added protection.

For an example - I used to be on a search/rescue team and we had a trailer that was used as a command center with an office. It was run off of generator power. I can't remember what I was hooking up, could have been a radio antenna cable or another AC line. I was kneeling down where our pass-through compartment was to run the line and as soon as I touched the trailer I got hit with 110v. Somehow I ended up completing the circuit to ground. I'd rather not replicate that experience. In this example the generator and the trailer both should be grounded (and were - that particular time the trailer was not - but therein is the point - a GFCI would have tripped and I wouldn't have got the shock I did).

Okay, so general purpose use, basically an extension cord from a generator.

I have a generator with the L14-30 outlet and an 80' feeder cable to an auxiliary input next to the main panel for our home. I also used to sell Briggs & Stratton backup generators (factory trained tech) and just let my ABYC electrical certification expire, so I do have a little formal training.

AFAIK there's no code requiring GCFI on extension cords, if I felt it were required I'd put it at the panel since it would protect the entire branch just like in my home. If I needed grounding for a generator supplied circuit I would be inclined to drive a ground stake in close to whatever I was powering and use that. All GCFI does is sense if there's a load that doesn't have proper grounding and trip to protect whatever life form happens to want to use that load.

In my experience GCFI devices fail far more often than they actually protect me, big faults will trip the main breaker as long as it's sized properly. If I have the opportunity to manage the circuits hooked to my supply I can certainly ensure proper grounding, verified with my meter if necessary. Any device which is suspect can easily be plugged into a household GCFI protected circuit before I take it out into the field.

The device you linked to should provide the protection you seek but any flaky ground connections should trip it, so you will need to make sure whatever equipment you're using has proper grounding anyway. If it makes you feel better then go ahead and order it, just realize you can buy an awful lot of copper ground wire for $160 bones....

I'm not a licensed electrician, just some guy on the Internet so my advice is worth exactly what you paid for it. If you want a professional opinion please contact someone who carries the proper license and insurance to go with it.

Cheers,

John
 
AFAIK there's no code requiring GCFI on extension cords, if I felt it were required I'd put it at the panel since it would protect the entire branch just like in my home. If I needed grounding for a generator supplied circuit I would be inclined to drive a ground stake in close to whatever I was powering and use that. All GCFI does is sense if there's a load that doesn't have proper grounding and trip to protect whatever life form happens to want to use that load.

Perhaps NEC doesn't specify GFCI as a "requirement", however OSHA certainly does - regulation over jobsite safety. Yea, that differs in environment than a home/shop/farm environment to some extent (those generally aren't "construction sites", but could be).

When I get a chance I'll dig a bit on what NEC says for GFCI. They certainly do have that for bathrooms and locations where there is water (kitchen sink area etc).

Thanks for sharing your knowledge. And yes, I know what you mean about GFCI's failing a lot. I've had the same problem on fixed outlets (and replaced outlets for that reason). One of the circuits here covers the garage and outside outlets and is GFCI protected. Christmas lights have a tendency to throw the GFCI and I've even had it go running power equipment.

I am hoping since the advent of GFCI breakers the quality has gone up in recent years. I do see there are some with adjustable set trigger currents so that alone would help with the frequency of trips - if it is too sensitive then bump up the trigger threshold.
 
Yes, both sensitivity and the tendency to fail at just the wrong moment are both reasons I don't like GCFI for the shop. At my home I have the ability to inspect cords and equipment, and to wear rubber boots if I plan on using electricity near water. Everyone should do whatever it takes to make sure their home shop and environments they control are safe and don't present any unnecessary hazards.

John
 
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