120 or 240 V, how do I tell?

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Old 10-03-17, 02:49 PM
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120 or 240 V, how do I tell?

I'm trying to buy a pool pump for a new above ground pool. I thought I had 240V breaker, but now I'm realizing the people we bought the house from did everything themselves, but very poorly and quite often incorrectly. So, I shouldn't assume anything. I've been looking online to try to figure out which I have for sure, but I've read a lot of things saying homeowners rig lots of stuff incorrectly and it may just "look" like one when it's really the other. I only have a cheap multimeter from Harbor Freight that isn't sufficient to measure this. Don't worry, not trying to rewire anything myself. Just need to know which pump to buy depending on voltage. Can anyone tell me for sure what I'm looking at based on this pic?
Thanks for any help.
 
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Old 10-03-17, 03:03 PM
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Welcome to the forums.

What is your question ?
Are you asking if the current breaker for the pool pump is 240v.... then you need to tell us which one it is.

That panel is a 120/240v panel with no room left.
 
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Old 10-03-17, 03:36 PM
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Oops, sorry. It's the top right breaker that's switched off in the pic. How do you tell for sure?
thanks.
 
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Old 10-03-17, 04:05 PM
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That top right breaker is a single 20A breaker which means the circuit is 120v.
 
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Old 10-03-17, 04:34 PM
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So does that mean the top left is a double and 240V? Also, what is the bottom left 15A? All 3 of those breakers are currently not used. I can buy a pump in either voltage, but I was leaning toward the 240 for some of its features.

Thanks, Pete. And thanks for not giving me a hard time for my limited knowledge.
 
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Old 10-03-17, 04:53 PM
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No.... the top left breaker is a full size 1" breaker. The upper right one is a half size breaker so that two can fit in one standard 1" space. A panel is only designed to hold xx amount of breakers. Usually the part number would be 1218 or 1224. The first number is full slots. You have 12. The second number is the total amount of circuits. You have 18. You cannot exceed the second number of half sized breakers. That number is on your panel.... and also on a diagram.

The breaker in the middle left side with the tie handle is a true 240v breaker.

Here's where it gets complicated. Looking at you panel.... breaker 1 is on leg A of power. Breaker 2A and 2B are also on leg A of power. Breaker 3 is on leg B. Breakers 4A and 4B are on leg B. It alternates every other 1" space.

When you see red and black wires from the same cable..... the red needs to go on one leg and the black MUST go on the opposite leg.

I see what looks like red and black pairs on the same leg. This may be incorrect as I think you have some circuits arriving there in conduit.

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Old 10-03-17, 05:01 PM
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The top two left seem to be two single pole breakers on a multiwire circuit.

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Old 10-03-17, 05:09 PM
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That is correct Ray. I see several MWBC's but it's hard to tell as there are extra red wires.
 
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Old 10-03-17, 05:32 PM
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You guys are great at explaining things and it all makes sense (I just didn't know it before!) So, if I'm choosing a pool pump, all of mine are 120V except for the tie handle (which is my A/C and definitely not going to be used for my pool pump,) correct?

So when you say I might have some red and black pairs on the same leg or that some circuits might arrive in conduit, does that mean the previous home owner messed up and I need to have an electrician come fix stuff?
 
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Old 10-03-17, 05:37 PM
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Look at breakers 1 and 3. Obviously those two wires.... the red and black.... are from the same cable. One wire is on leg A and one is on leg B. That is the proper way to connect that circuit. Code now dictates that the 1 and 3 breaker handles be tied together to shut both off at the same time since they share a common neutral. Basically that is two 120v circuits sharing a 240v wiring method called multi wire branch circuit.

If you look at the other side of the panel.... there are red and black wires all over the place. IF they come from the same cable.... they also must be on different legs of power. I can't see all those cables clearly.
 
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Old 10-03-17, 05:40 PM
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The main breaker at the top looks to me like a GE breaker and I can clearly see some GE breakers on the left side of the panel. Is this a GE panel? Is there a GE emblem somewhere on either the panel door latch or on a label inside the door? Assuming that I am right and this is a GE panel, you have a problem. The tandem breakers on the right side are either Siemens or Murray breakers and shouldn't be in that panel.
 
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Old 10-03-17, 09:03 PM
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Okay, Pete, that all makes sense, too. Thank you for explaining it to me.

Does what CasualJoe said about the different brands really matter? The main and whole left side are GE, and the right Murray (no label on that odd duck in the middle.) They are not compatible/interchangeable?

Did I mention our house is pretty old? I looked for a diagram. There is a homemade table mapping each breaker to all outlets and switches taped to the inside of the cover. Underneath that was a diagram that is now 1/2 disintegrated, pic attached. It does say Line A and Line B, so I understand that now, but it also says 12 poles (6 per phase leg), 20 poles (10 per phase leg), so apparently 2 of my breakers could be split into 1/2 size "twins" for a total of 20, is that correct?

Since you were so helpful, I did the work of tracing each wire and found (using the labels in your pic) that all the red/black pairs originating from the same cable do have a leg A/B match. (They happen to be these pairs: 1A/3B, 2B-A/4A-B, 6B-A/8B-B, 10A-A/12B-B, 10B-A/12A-B.) The only one I don't know about is 5A/7B. Those 2 wires come from the same cable which only has 3 wires, black/white/copper. The white has been covered in black tape. Does that mean they used the white like a red and the ground like a neutral?

All the other wires, (9A, 11B, 2A-A, 4B-B, 6A-A, 8A-B,) come from their own separate cables with no red/are not paired. Is this a problem?

And, yes, about 1/3 of them are not grounded.

Thanks for already answering the voltage question for the pool pump. The above questions are really just to gauge how safe we are/whether or not I should call an electrician.
 
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Old 10-03-17, 09:19 PM
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They are not compatible/interchangeable?
Pretty sure from your label it is GE. They are not rated for use in your panel. That would be a NEC violation because they are not used for their intended purpose. Should there be a fire it would be grounds to deny an insurance claim. Bottom line they may fit but were never tested to determine if they work correctly in your panel. They need to be changed to GE half size breakers. (GE doesn't sell tandem breakers.)

Those 2 wires come from the same cable which only has 3 wires, black/white/copper. The white has been covered in black tape.
That is to indicate it is used as a hot not a neutral. That is an NEC requirement when a 2-conductor cable is used for 240 volts.

Does that mean they used the white like a red and the ground like a neutral?
No. A 240 volt supply has no neutral. Bare is always ground.
 
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Old 10-03-17, 09:33 PM
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Thanks, ray.

So the only question, are the ones not paired up okay? Looks like I should call an electrician to get up to code anyway, just a question to satisfy my curiosity I guess.

You guys are so helpful!!
 
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