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Splitting 120V off 240v - am I doing it right? And who is John Galt?

Splitting 120V off 240v - am I doing it right? And who is John Galt?

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Old 09-05-17, 07:46 PM
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Splitting 120V off 240v - am I doing it right? And who is John Galt?

Hello everyone,

I have an existing GFCI protected 120V line to my backyard. It runs from the breaker box in the basement via 8 gauge 4 wire direct burial cable to an outdoor J-box, on a 20 amp GFCI breaker, and after the J-box there are three downstream 120V outlets on 12 gauge wire connected to the 8 gauge wire. The red wire in the 4 wire cable is not used and is curled up outside the breaker box in the basement and inside the J-box in the backyard. On this circuit are a couple of 12v low voltage transformer for outdoor lights (they pull very little amperage) and a 120v 0.5HP pool pump for our waterfall that pulls (I think) about 8 amps. I need to upgrade the waterfall pump to a more powerful 1.5HP motor that is wired for 230V and would pull about 8 amps on a 240V circuit per the manufacturer specs.

My plan is to convert the existing 8 gauge wire 120V circuit to 240V by removing the single pole 120V GFCI breaker and installing in its place a two pole 240V 20 amp (or 30 amp) GFCI breaker in the existing breaker box in the basement (there is plenty of room) and setting it up with green ground, white neutral and the black and red wires as hots. Then, in the backyard, at the terminus of the 8 gauge wire in the existing J-box, I would install a new outdoor weather protected breaker box, where I would install a second 20 amp (or 30 amp) 240V breaker, plus a 120V breaker, and then wire it so as to split off from the 240V line a 120V line through the 120V breaker. Then I would simply connect the 120V line to the existing 12 gauge 120V circuit (which I disconnected from the old J-box) to power the low voltage transformers, and then I would run a new separate 240V line down to a new locking receptacle for the new 230V waterfall pump motor.

As I understand it, since I have a 4 wire cable, I can use the white shared neutral for both the 240V and the 120V circuits in the second, new, outdoor breaker box. I can, if necessary, install a ground rod next to the new outdoor breaker box for ground purposes but since the green ground is in the 4 wire circuit I think I can use that instead. The end result - I hope - is a split circuit with GFCI protected 240V running from the house to the outdoor breaker box, then a separate 120V line for the existing outdoor low voltage lights and a separate 240V line for the waterfall pump. All of this will be installed in buried conduit, none of it will be direct buried cable.

Questions - (1) is this feasible? (2) If not, what is wrong with my circuit design? (3) How does one "split" off a 120V line off the 240V line in the outdoor breaker box I plan to add? (I am told this is easy but not sure how it is wired). (4) What gauge wire should I use for the 240V line from the outdoor breaker box to the 240V receptacle for the pump motor - is 12 gauge okay? (5) Should I use a SECOND GFCI breaker in the outdoor breaker box for the 240V and 120V circuits or is the GFCI breaker in the basement box which will feed the 240V line from inside sufficient GFCI protection? (6) Who is John Galt?

Thank you in advance for any and all learned advice. My father taught me a lot about electrical, plumbing, etc. but I am not an expert, and am still trying to figure out if my plan makes sense. I am not looking to cut corners on cost, so whatever the cost is for the components is not an issue. So thank you for your patience with me. Regards to all,
Ross
 
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Old 09-05-17, 09:05 PM
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Welcome to the forums.

Your ideas are sound. No ground rod required at remote "sub panel". At the sub panel you will connect the hots to the two bus lugs. The white connects to an insulated bar and the ground connects to a bar attached directly to the box. The neutral bar will be already installed and you'll need to install a ground bar. The white/neutral wiring and the ground wiring cannot touch. Be sure to use a NEMA 3 weatherproof sub panel.

A 2P20A breaker should be fine for the pump using #12 to the receptacle. A single 20A breaker is fine for the existing circuit. You will need at least a 2P30A GFI breaker in the main panel. When wiring the breaker..... the white lead from your 4 wire feed goes to a marked terminal on the breaker. Then there should be a white lead from the breaker that goes to the neutral bar.
 
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Old 09-06-17, 12:02 AM
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Assuming your question concerning John Galt is legitimate, John Galt is the protagonist in Ayn Rand's seminal work, Atlas Shrugged. The book is in excess of 1400 pages but, in my opinion, is one that everyone should read at least once. Agree or disagree with Rand's philosophy, she does make a person think.
 
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Old 09-06-17, 03:33 AM
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Thanks to PJMAX for confirming I can do this the way I plan. I have run all of my other outdoor circuits (all 120V) but have never wired up a 240V circuit. I tried to find local electricians who would help for some quick cash, but for this small project I could not find any takers. So I figured okay I can do this....... And to Furd, yup, you win the prize. Ayn Rand's seminal novel...... A great read (except for John's speech in the middle of the book - I think it runs to 150 pages more or less). This is a great forum, thanks again.
 
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Old 09-06-17, 04:40 AM
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The problem is the grounding conductor in the cable is bare and needs to be insulated for the pool. You win need to do some rework .
 
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Old 09-06-17, 10:39 AM
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new locking receptacle for the new 230V waterfall pump motor.
No pool here. OP mentioned using a pool pump for his fountain.
 
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Old 09-06-17, 03:48 PM
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It is a PondPro, external, self-priming, 0.5HP 120V pump that can be used for ponds, waterfalls or pools. It is set up very similar to a pool system, with bottom suction intake in the bottom waterfall basin, a Hayward DE pool filter and a UV cleaner to keep the waterfall water squeaky clean. The problem is the head height is so high due to actual height of the top water fall (about 25 feet) plus there are a few 90 degree elbows in the 3 inch supply line, that the 0.5HP motor just doesn't move enough water, hence I am upgrading to a 1.5HP motor, but it's a 240V motor, not 120V.
 
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Old 09-06-17, 04:34 PM
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Actual pool wiring would require an insulated ground.
 
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Old 09-08-17, 01:16 PM
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Thanks Paul, that's interesting, why would a ground need to be insulated? I mean, it's a ground wire and they usually aren't. Not sure I understand the electrical risk of an uninsulated ground wire in the 240V circuit (if it was a pool not a water fall). In fact, one could sit on the edge of the bottom basin of the waterfall and dangle their feet in on a hot day, so maybe I should treat it like a pool? Thoughts and recommendations would be appreciated. Thank you.
R
 
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Old 09-08-17, 01:59 PM
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The code usually doesn't give the reasons why certain things are required, just that they are required. I think it's fair to speculate that the insulated ground is required to reduce copper corrosion and loss of integrity of the conductor that could occur when exposed to the wet, salt and chlorine environment around the pool. Or perhaps to provide a visual cue of the green ground wire to any future service people.

If it was at my house I would at least want GFCI protection on the fountain equipment for the very reason you mention. Someone can stick their hands or feet in the fountain and potentially be exposed to shock if the pump or lighting has failed. The other requirements for pools like equipotential bonding are probably overkill as these really address shock potential when a person's body is in the water and they grab something to climb out.

And John Galt is an interesting character as a thought experiment, but ultimately Rand as a profound misanthrope herself comes from a place of such cynicism that her literary works come off quite one-dimensional to this armchair critic. I'll still always turn up a Rush song when it comes on though. Enough electrical book talk?
 
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Old 09-08-17, 02:41 PM
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Thanks Ben. In fact, I did have the bottom basin of the waterfall bonded - it's all concrete but in addition to the bottom suction for the pump, it has a skimmer suction as well on the side, a small one designed for jacuzzi style in ground hot tubs. There is a very neat kit available that uses a stainless steel plate with a threaded rod/stud off the back - you drill a hole through the back of the skimmer port, the plate mounts flush inside below water level, and you attach your bonding wire to the stud on the back and seal it with silicon - works like a charm, it doesn't block the skimmer basket. Knowing that people will stick their legs in this thing I tried to meet as many pool code requirements as I could. I'll do same with the electrical to the extent I can. Since I am running new wiring to a 240V receptacle anyway, I can run insulated ground in the same conduit with the black and white to the outlet.
 
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Old 09-08-17, 02:52 PM
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One more question to Pete (sorry to be a pain), but at the sub panel where my 4 wire line comes in, I wire the black and red to the two main lugs - got that. I wire the green to the ground bar - got that. I wire the white to the breaker, and from the breaker I connect the white lead to the neutral bus - so does all of this mean that what I ultimately run from the breaker to the receptacle is black and red, and green ground, no white? The black and red each connect to one of the side lugs on the receptacle (hots), and the green connects to the round ground lug, and there's no white to the receptacle - is that correct? I will look at my Basic Wiring book too, but wanted to check here too. Thanks!
 
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Old 09-08-17, 03:43 PM
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Originally you mentioned a GFI breaker in the main panel. My wiring description was aimed towards that setup.

If you use a regular two pole breaker in the main panel..... you will then need a two pole GFI breaker for the pump and a single pole GFI for the misc circuit.

Your 240v receptacle will have a red, black and green/bare wiring.
Your misc circuit will have red or black and white and green/ground.
 
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Old 09-09-17, 01:04 AM
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...ultimately Rand as a profound misanthrope herself comes from a place of such cynicism that her literary works come off quite one-dimensional to this armchair critic.

A fair statement in my opinion. Read a few of the "tell all" biographies of Rand and you soon learn that no matter how much her fans worshiped her it wasn't enough. I still think her "philosophy" IS interesting, especially as you put it as a thought experiment, but being an absolute adherent to it in today's world, or even her world of fifty years ago is simply insane.

Okay, no more on Ayn Rand.
 
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Old 09-09-17, 05:10 AM
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Yes, confirming I am installing a 2P240V GFCI breaker in my main panel. I want the entire circuit protected on GFCI from the main panel. Then, at my sub-panel I plan to use to a regular 2P 240V breaker for the waterfall pump circuit and a regular 1P 120V breaker for the misc circuit. So based on that description it sounds like I connect the white to the neutral bar and only run red, black and green ground to the waterfall pump outlet. Two more dumb questions - 1) There are different kinds of 240V outlets available, I assume I would use one that is set up for three wires - red, black, green ground, right? and 2)does it make sense to use GFCI breakers in the sub-panel too or is that unnecessary and redundant? I assume the latter, but sometimes the most obvious answer isn't necessarily correct. Thanks again, this is a great resource. Cheers, Ross
 

Last edited by rossvesq; 09-09-17 at 05:12 AM. Reason: add question
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Old 09-09-17, 11:55 AM
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Using back to back GFI devices results in unpredictable operation. Best to use a single GFI protection device per circuit. Either the single one at the main panel or the two at the subpanel.

You'll probably need an in-use cover over your pump receptacle.
Does the pump come with a cord and cap ?
It may be a standard 20A 240v plug.
 
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Old 09-21-17, 03:05 PM
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Thanks for the feedback Pete. Sorry for long delay, i was traveling out of the country for a couple of weeks. Yes, that's what I thought about back to back GFIs, so thanks for confirming. Yes, the pump motor comes with a cable, I need to purchase a plug for it - either 120 or 240, and obviously I will go 240. The photo you attached is what I had in mind, combined with a weatherproof cover box. So it looks like I am on the right track. Again, many thanks, I do appreciate all the great advice.
R
 
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Old 10-06-17, 09:03 PM
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Pete, one last question. I am ready to finalize the wiring. But in the main breaker panel in the basement, the neutral bar and ground bar are the same - both the neutral whites and bare grounds are connected to the same bus bar. If I understand correctly, I take the 4 wire line from the main breaker to my subpanel, connect the black and red hots to the hot terminals, connect the white to the neutral bus bar already installed in the subpanel cabinet, and then I connect my ground to the new ground bar that I added to the subpanel cabinet.

Question - Does it matter that the white and ground are both connected to the same bus bar in the MAIN breaker panel? If not, then I think I am good to go. But it made me wonder why I would need to separate them at the subpanel if they are already connected to the same bus bar in the main panel.

Many thanks for all your help.
Ross
 
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Old 10-06-17, 09:30 PM
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Yes.... the white and ground connect to the same bar in the main panel. This is the only place they are combined. This is done to insure that you have a neutral and ground path to your main source of ground which is located at the main panel.
 
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Old 10-07-17, 04:09 AM
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Thank you!! I appreciate all your help!!
 
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Old 10-07-17, 01:37 PM
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Success! All is good, all works, all looks great. Thanks again for all the support.
Ross
 
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Old 10-07-17, 01:52 PM
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Well done.... a good weekend project completed.
 
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