Inline GFCI w/ March pump. This safe?

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Bizoune

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Is it ok/recommended to add an GFCI on a march pump toolbox if the power is already coming from a GFCI outlet? I'm thinking of adding one directly on the toolbox in case I ever take my equipment where a GFCI is not available, so I can then use it safely.

So my circuit would look like this:

GFCI in garage > GFCI on toolbox > on/off switch > pump > back to GFCI in the garage

Is this possible or will 2 GFCI outlets back to back screw up the whole outfit?
 
I have my GFCI's and switches mounted on my brew bench:

DSCN0048.jpg


In my house, there is a GFCI outlet "downstream" from another GFCI (bathroom) outlet. The only odd thing I have seen is that if one trips, the other trips. Which, when I think of it, is probably how it should work.
 
The only odd thing I have seen is that if one trips, the other trips. Which, when I think of it, is probably how it should work.

That would be expected. If there is a fault both outlets are going to see it and both will trip. You *might* get an instance where the one on your panel trips and the one further back on the house does not, but I would expect them to both go at the same time in most cases.
 
I don't think 2 gfci in tandem is a good thing. I believe you will continue to trip the gfci. I am not an electrician, but I have heard about this on home improvement shows.
 
I don't think 2 gfci in tandem is a good thing. I believe you will continue to trip the gfci. I am not an electrician, but I have heard about this on home improvement shows.

I'm not an electrician either but this isn't really true. You can have multiple GFCI's on one circuit but it isn't needed. A GFCI will protect all downstream outlets so they all essentially become GFCI's. When you have multiple GFCI's, when one trips, you have to reset all of them.
 
2 GFCI's inline isn't going to hurt anything but your wallet! Figure that most home improvement stores will sell these between $15 and $18, while a regular outlet is $2. So as long as the main feed comes to the GFCI and all other outlets are fed off of it they will all be ground faulted plugs (provided you remove the little sticker off the top legs of the GFCI outlet and connect the other outlets there so that they will be protected).
 
Thanks for all the info. Anybody have the schematics to wire this up?
I'm an geeky accountant, so forgive my ignorance on electrical circuits. I'm assuming black on black, white on white etc. I dont' have an GFCI outlet with me but isn't there 3 or 4 screws on the unit to receive either one of the 3 wires coming for the extension cord. Any way I can not screw this up?
 
Thanks for all the info. Anybody have the schematics to wire this up?
I'm an geeky accountant, so forgive my ignorance on electrical circuits. I'm assuming black on black, white on white etc. I dont' have an GFCI outlet with me but isn't there 3 or 4 screws on the unit to receive either one of the 3 wires coming for the extension cord. Any way I can not screw this up?

Someone will correct me if I'm wrong but I believe there are 5. Two for the line coming in, two for the load going to the down receptacles, and a green one for the ground.

The GFCI should be labeled with a load and a line. The wires coming from the box should be in the "line" and the wires going to the downstream receptacles should be in the "load" side. I'm pretty sure thats how it goes.
 
Someone will correct me if I'm wrong but I believe there are 5. Two for the line coming in, two for the load going to the down receptacles, and a green one for the ground.

The GFCI should be labeled with a load and a line. The wires coming from the box should be in the "line" and the wires going to the downstream receptacles should be in the "load" side. I'm pretty sure thats how it goes.

Edit: removed previous response. The pic is accurate. It's showing the two lower terminals for connecting to the source (LINE) and the two upper terminals (called LOAD) for feeding downstream outlets.
 
That's a neat pic. Do you think you could draw one with a circuit in this order, for the electrically challenged like myself?

source > gcfi outlet > on/off switch > pump

What if I want 2 switches? One that brings power to the GFCI outlet on my toolbox and the other to the pump? So the #1 switch would have to be on for the #2 switch to be able to activate the pump.

Can you draw this up as well, if you've got a few minutes?

Thanks everybody!
 
Throw in a 3-way switch and you'd have what you want.

I'll try to do a quick drawing when I have a few minutes.

M_C
That's a neat pic. Do you think you could draw one with a circuit in this order, for the electrically challenged like myself?

source > gcfi outlet > on/off switch > pump

What if I want 2 switches? One that brings power to the GFCI outlet on my toolbox and the other to the pump? So the #1 switch would have to be on for the #2 switch to be able to activate the pump.

Can you draw this up as well, if you've got a few minutes?

Thanks everybody!
 
Here.

3-Way switch toggles from non-CGFI to CGFI. Also turns on/off the pump when you throw the switch (added bonus!) :D

11hfqja.jpg

Is the GFCI outlet in this pic always on or is it controlled by the 3 way switch? Is the three way switch required or can u use a single pole? I am attempting to wire an extension cord (source) to a GFCI outlet then to a switch to control my march pump. I have the box and switch shown in this video.

 
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If you have two GFCI than one will not protect you. This would make one cancel the other one out. Look at a bathroom if one outlet is the GFCI the other is not. BAD to have on the same circut...
 
If you have two GFCI than one will not protect you. This would make one cancel the other one out. Look at a bathroom if one outlet is the GFCI the other is not. BAD to have on the same circut...

Absolutely wrong in every way.

GFCI's do not/can not "cancel" each other out. It's not possible for such a thing to happen.

The reason the bathroom will have onr GFCI and one regular outlet is because the regular is daisy-chained off of the GFCI and inherits protection from it. There's no need for the second one to have a GFCI circuit in it.
 
Just to add a little more fuel. I worked for years in an industrial environment. Our safety procedure manual called for "double ground fault circuit interrupters" or 2 GFCIs inline, anytime there was work to be performed in a "wet environment". The thought was, redundancy. While this is probably unnecessary, in 35 years, and 100ks manhours, no electrical incidents due to GFCIs (or lack thereof). - Dwain
 
Walker said:
Absolutely wrong in every way.

GFCI's do not/can not "cancel" each other out. It's not possible for such a thing to happen.

The reason the bathroom will have onr GFCI and one regular outlet is because the regular is daisy-chained off of the GFCI and inherits protection from it. There's no need for the second one to have a GFCI circuit in it.

This would be the same as canceling out a GFCI outlet too. One trips in the line all within the daisy-chain will trip or cancel each other out...
 
This would be the same as canceling out a GFCI outlet too. One trips in the line all within the daisy-chain will trip or cancel each other out...

I guess I don't understand what you mean by "cancel each other out". ???

You presented it as if it was BAD to have two of them in series. And it's not bad at all. It's redundant and unnecessary, but not bad at all.
 
I was thinking along the lines of this (below) for 1 CGFI'ed and 1 NON-CGFI'ed.

156wyt0.jpg


(sorry for the crude drawing, I made it quick).

M_C

OK question, WHY? why would you not want GFCI?, sure sometimes it is unnecessary, but i don't see why you if you have the GFCI you wouldn't do it?
 
OK question, WHY? why would you not want GFCI?, sure sometimes it is unnecessary, but i don't see why you if you have the GFCI you wouldn't do it?

+1 This is a mystery to me also. The possible problem I see would be mistakenly plugging into the non-GFCI receptacle which would offer no protection at all. The floor in my brewing area is usually wet, so a GFCI is mandatory for me.
 
I want the gfci... I was just hoping to protect the pump with it in the circuit. Something like: source > gcfi outlet > on/off switch (control the pump) > pump. Any chance someone could work up a wiring diagram for that? I will have the gfci and the switch in a double gang box (see video previous page) the pump would be hard wired to the switch. Thanks in advance for your help!
 
I've seen GFCI's that were too sensitive to handle a high start load, especially with pumps, refrigeration units, etc. Or sometimes you don't really need the protection, e.g. light bulb/lighting, etc.

M_C
OK question, WHY? why would you not want GFCI?, sure sometimes it is unnecessary, but i don't see why you if you have the GFCI you wouldn't do it?
 
Just to add a little more fuel. I worked for years in an industrial environment. Our safety procedure manual called for "double ground fault circuit interrupters" or 2 GFCIs inline, anytime there was work to be performed in a "wet environment". The thought was, redundancy. While this is probably unnecessary, in 35 years, and 100ks manhours, no electrical incidents due to GFCIs (or lack thereof). - Dwain

I believe that info is actually incorrect. A "Double Ground fault circuit" is actually what it sounds like... 2 ground wires. This is the standard in hospital wiring and many industrial applications.

You will have the ground from the panel just as you would in a house, but then an additional ground is brought in from a grounding rod installed throughout the facility. For example in a Hospital, each "department" or "circuit" will have both a home run w/ground and a second ground connected to a grounding rod somewhere in that area. So what you end up with in the box (using 110v as example) is a Hot, a Neutral, and 2 grounds connected to 2 grounding sources.

That way is for some reason one of the grounds fails the other is there to protect you.
 
This would be the same as canceling out a GFCI outlet too. One trips in the line all within the daisy-chain will trip or cancel each other out...

That actually depends how you wire it...

GFCI_receptacle.jpg


Imagine the outlet on the left is another GFCI and you have it wired in the same way then your statement is correct. When the GFCI outlet on the Right trips then the second GFCI (that we are imagining is on the left) would not work.

BUT....

If you daisy chained the 2 GFCI outlets off the "Line" side of the GFCI outlets then the GFCI's would trip individually.

Only when you pull power from the "Load" side of a GFCI are daisy chained outlets protected from the first GFCI. This is done in homes for the simple cost saving aspect. A GFCI will generally run you $18 at your local box store and a regular outlet is $2... So it's just cheaper to have 1 GFCI in a bathroom and have the other outlets fed off the "Load" side than to have multiple GFCI's. So if you have 3 outlets in your bathroom... $22 for all three is a lot better than $54!

Hope this helps.
 
I believe that info is actually incorrect. A "Double Ground fault circuit" is actually what it sounds like... 2 ground wires. This is the standard in hospital wiring and many industrial applications.

Actually, the procedure manual called for low voltage equipment when working in a wet environment. They had almost anything you could imagine in low voltage. However, if you had to use something they didn't have in low voltage, after a full Safe Operations Committee review (which typically included a member or members that were specialist in whichever field was being discussed), they could grant an exception or variance. Whenever they did, the manual specified to plug one GFCI into a power supply, the other GFCI into the first GFCI and then the equipment into the second GFCI. I'm not sure what the correct Technical jargon is, but that's what the manual said and illustrations were given.
 
Actually, the procedure manual called for low voltage equipment when working in a wet environment. They had almost anything you could imagine in low voltage. However, if you had to use something they didn't have in low voltage, after a full Safe Operations Committee review (which typically included a member or members that were specialist in whichever field was being discussed), they could grant an exception or variance. Whenever they did, the manual specified to plug one GFCI into a power supply, the other GFCI into the first GFCI and then the equipment into the second GFCI. I'm not sure what the correct Technical jargon is, but that's what the manual said and illustrations were given.

WOW... I'm not sure what you would call that, other than redundancy for the sake of redundancy.... Either someone was previously sued or y'alls Lawyers were very nervous people. LOL
 
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