# 120 vs. 240 pool pump



## Bkessler (Feb 14, 2007)

If you did I would not get it.


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## brian john (Mar 11, 2007)

And I bet you could not persuade her of he wrong.


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## nap (Dec 26, 2007)

I know electricians that believe it as well. If it made her happy and she hired you, let her live in her delusion. It can save install costs, sometimes.


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## Jeff000 (Jun 18, 2008)

Being a bit new to this can you explain. 
I am assuming 6amps 240 volt is just 6amps per 120 volt phase, for a total of 12 amps still right.


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## nap (Dec 26, 2007)

12 amps X 120 volts =1440 watts

6 amps X 240 volts=1440 watts

there is no amps per phase situation.


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## micromind (Aug 11, 2007)

The opposite of this is a good-sized motor that someone wants wired up 110, because 220 is dangerous. 

It never ceases to amaze me what people can be duped into believing, especially in the name of safety. 

Rob


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## waco (Dec 10, 2007)

Let's see now, smaller wire and plenty of amps to spare for heavy loads. I agree with her, although not for the reason she stated.


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## Jeff000 (Jun 18, 2008)

nap said:


> 12 amps X 120 volts =1440 watts
> 
> 6 amps X 240 volts=1440 watts
> 
> there is no amps per phase situation.


 
Ah, I should have known that, just didnt click  

Thanks.


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## heel600 (Oct 31, 2007)

*240 pump*

as long as we're on this topic, does anyone see a problem with running a 240v circuit (2 hots and 1 nuetral) to a timer, and run the 2 hot legs to a pump, and just one leg and the nuetral to the GFI rec?

Pump only draws 7 amps @ 240v.

Not how I normaly do it, but there were only 2 spaces in the panel.


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## Jeff000 (Jun 18, 2008)

heel600 said:


> as long as we're on this topic, does anyone see a problem with running a 240v circuit (2 hots and 1 nuetral) to a timer, and run the 2 hot legs to a pump, and just one leg and the nuetral to the GFI rec?
> 
> Pump only draws 7 amps @ 240v.
> 
> Not how I normaly do it, but there were only 2 spaces in the panel.


On site we are hooking up a 240v heatpump with 10/3, but it stops for a 120v plug thats in the access hatch for the heatpump first. I doubt that plug will every get used so dont see a problem. 


But a plug on a pool deck might get used more often, and if it something like power tools there could be a problem. 
Also while I have not hooked up a pool pump, why would it be on a timer? or in the states is leaving the pool stale overnight common? 
Also when a motor kicks on it will draw a lot more then 7amps, so having something else plugged into that circuit might cause a problem when the motor first kicks on, but be fine the rest of the time.


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## randomkiller (Sep 28, 2007)

Jeff000 said:


> On site we are hooking up a 240v heatpump with 10/3, but it stops for a 120v plug thats in the access hatch for the heatpump first. I doubt that plug will every get used so dont see a problem.
> 
> 
> But a plug on a pool deck might get used more often, and if it something like power tools there could be a problem.
> ...


So what your saying is you have an outlet on a 30 amp breaker that you believe really won't get used. It isn't code compliant anywhere I have worked. Let me guess, it's also a 15 amp device?


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## wirenut1110 (Feb 12, 2008)

heel600 said:


> just one leg and the nuetral to the GFI rec?
> 
> Pump only draws 7 amps @ 240v. but there were only 2 spaces in the panel.


The disconnect/gfi needs to break all ungrounded conductors, if the ground-fault trips the pump is still energized. If there's only 2 spaces, what's wrong with using a 2 pole breaker or a small sub-panel? Also "sharing a neutral" like this, I believe, will cause your gfi to trip as in a MWBC.


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## Jeff000 (Jun 18, 2008)

randomkiller said:


> So what your saying is you have an outlet on a 30 amp breaker that you believe really won't get used. It isn't code compliant anywhere I have worked. Let me guess, it's also a 15 amp device?


Is on a 2 pull 20 amp breaker. 20 amp plug will be installed. 
I dont think it would ever get used, to me its dumb, if your doing maintenance on the heatpump I could see it getting used, but if your doing that you should really have the breaker turned off so the plug would be dead anyways. 
The plug is in the ceiling, in the access hatch for the heatpump, so its not a convenience plug as its not convenient. 

I have no idea about it being code compliant, I am just an apprentice doing what I am told, I know my boss questioned it, and is trying to get rid of it. Its in the engineers specs to have it this way. We just have a loop at the plug box right now in hopes that it is removed, we will then just go back and ziptie the bx out of the way and take the box out. 

I am curious as to why its not code though. I'll ask about it today.


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## Jeff000 (Jun 18, 2008)

Randomkiller, you post had me questioning what I was told, so I looked in the code book (which I need to get more familiar with so it doesnt take me so long to find what I need). And then looked at the prints, seems the main prints have the box in the access hatch being a disconnect switch, and not a plug, but then the suit drawings have it listed as a plug. 
Upon bringing this up with the boss he said that a disconnect made more sense then the plug. But as far as I could tell in the code book the heat pump doesnt need a disconnect. 
But why didnt one of the 3 journeymen that have looked at the prints and even helped in the suits not noticed a plug like that is no good??


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## randomkiller (Sep 28, 2007)

Jeff000 said:


> Randomkiller, you post had me questioning what I was told, so I looked in the code book (which I need to get more familiar with so it doesnt take me so long to find what I need). And then looked at the prints, seems the main prints have the box in the access hatch being a disconnect switch, and not a plug, but then the suit drawings have it listed as a plug.
> Upon bringing this up with the boss he said that a disconnect made more sense then the plug. But as far as I could tell in the code book the heat pump doesnt need a disconnect.
> But why didnt one of the 3 journeymen that have looked at the prints and even helped in the suits not noticed a plug like that is no good??


It depends on experience and how much they care about what they are doing. Some guys will blindly do as told and never care about what is right. By code you need a means of disconnect with in sight for the heat pump or any type of 240v appliance for that matter. You also need a light and outlet for any mechanical equipment (RTU, furnace,heat pump,etc).


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