Need help electrical gurus - part identification

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Power went out today. Whenever it cycles back on, this breaker usually starts giving a loud buzz. It also may happens if I cycle my pump on/off.

I was told it is a Square D double pole breaker. I’m not sure what that means. My friend/neighbor had told me that he thinks it has to do with the contacts. When it is pulling power, it’s not catching smoothly and making a clean contact. I tightened down all of the wire screws if, if that’s what you call them, as that usually helps. Or, I will have to turn the power on/off a few times and that may do it.

I think the part needs to be replaced. However, I have no idea what this part is exactly. I was hoping to buy it and have an electrician install it or maybe my neighbor.

Above this part, you’ll see a switch labeled sweep. That actually is not the switch. The switch is directly opposite on the left, Not shown in the picture. When it is flipped off, there is no power traveling to this breaker.

any thoughts on what this part exactly?
 

swamprat69

Well-known member
Mar 30, 2019
169
Las Vegas, NV
That is not a circuit "breaker" , circuit breakers are in your panel to the left and you have 2 double pole and 2 single pole ciruit breakers. That looks more like a 3 pole contactor in which you are only using 2 poles, although it is hard to tell without seeing all of the wiring to it inside of the box it is in. The buzzing that you are hearing is a sign that it is not pulling in and seating completely when it is powered. This can be due either to wear or dirt/insects obstructing movement when it is powered. If you pull the part, there should be a label on one side or the other that will give you the coil voltage and the amp rating for the contacts. In your photo, I cannot see the wiring connections to the coil, but if it is turned on by the unmarked switch to the left of the "sweep" switch I suspect that it may have a line voltage coil rather than a low voltage (24V) coil. You can replace it with a part that has identical coil voltage and contact amperage ratings.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Thanks for the reply swamprat69. Yeah electrical stuff is a foreign language. I never knew they were such things as contactors, let alone 2 or 3 pole devices.

I Looked up on Google and I see some similar to what I have, although not an exact match. So is the only way to locate exactly what I need to turn off the power and take out the current magnetic contactor? I mean, can I already just assume it’s a 240 V 40 amp 3 pole magnetic contactor when buy some universal tape to fit in there?
 

swamprat69

Well-known member
Mar 30, 2019
169
Las Vegas, NV
Not being able to see all the wiring, I wouldn't assume anything. Best bet would be to turn off all power and double check that power was removed with a multimeter, then remove contactor and look for the label. Replace contactor with one that has the same coil voltage and contact amperage ratings.
 

Bama Rambler

Mod Squad
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Jun 22, 2009
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SouthWest Alabama
Most any contactor of sufficient rating will work, but you must know the coil voltage. It's most likely either 120 VAC or 240 VAC. Since it's energized by a switch it could be either, so you really need to know.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Thank you both so much.

Even with out removing the contactor, I think it has to be 240. If it is 240 and 40 A, are coil ratings different for different contactors?

I’m asking this because I figured maybe I should just have a few different models on hand that way if I remove it or my more experienced pool friend/retired engineer, that way it could just be swapped out instantly rather than taking out such an old contactor and having to put it back in and then order a new one and take it out again.

Let me upload you some other pictures I’ve taken over the years of this whole set up. This sub panel is connected to my main panel in the garage.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
DD72820A-B9AA-4E47-960A-016DF694106E.jpeg
If look at the top of this picture that brown metal pipe coming down that feeds this entire subpanel is 240.

while I understand this is not gonna provide the coil rating for the contactor, I just figured I’d give additional information as perhaps it reveals to you experienced electrical buffs the energy rating for the contactor.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Here’s a picture of the at the subpanel in my garage that controls the subpanel in the backyard. This one in garage shows a 30 amp breaker to the subpanel in the backyard. In one of the pictures in post #1, my subpanel, in my backyard is open. The top breaker is 20 A.

However, I still am not sure how any of this could correlate with the amperage and coil rating of my 3 pole magnetic contactor. I’m just trying to figure out a way to determine the coil rating and amperage of this magnetic contact her without pulling it. That way I could have a few different ones on hand and return the ones that don’t work.1FD41CDF-71D8-46BF-A4F0-7446304B359E.jpeg
 

Bama Rambler

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Jun 22, 2009
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The contactor rating is for the actual contacts rating and doesn't necessarily have anything to do with the coil voltage. While it's likely 240 volt coil voltage it could also be 120 volts. If you want to have a contactor there no matter which coil voltage you have you could buy one of each.

If it were me, I'd take a light and mirror and see if I couldn't tell what the coil voltage of that contactor is. You may even be able to get your phone at a angle where you could get a good enough picture to tell what it is.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Very clever Bamba Rambler. Didn’t think about the mirror or using my phone idea. When you said “If you want to have a contactor there...,” are you saying that it’s optional/not necessary? I inherited this pool. While I have an understanding of all the equipment and its function, the electrical stuff such as this still eludes me. I actually don’t know why this contactor is there and/or if it is necessary. If it’s not, all the more better. I don’t know what a contactor is or used for? And then, if it’s not necessary, I wouldn’t even know how the heck to override it and splice all the wires together.

Perhaps they had the contactor installed when the sweep booster pump was being used. Maybe to provide some sort of protection for the pool pump so that the pool pump has to run if the booster pumps on. I am just shooting blanks right now. I don’t know it’s function.
 
Last edited:

Hootz

Bronze Supporter
Feb 5, 2018
176
Rogers, AR
You have a robot cleaner per your signature...if you don't use a pressure cleaner and the only purpose of the contactor is to run a booster pump you can most likely eliminate that circuit ( and the contactor).
 

Bama Rambler

Mod Squad
TFP Expert
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Jun 22, 2009
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SouthWest Alabama
Very clever Bama Rambler. Didn’t think about the mirror or using my phone idea. When you said “If you want to have a contactor there...,” are you saying that it’s optional/not necessary? I inherited this pool. While I have an understanding of all the equipment and its function, the electrical stuff such as this still eludes me. I actually don’t know why this contactor is there and/or if it is necessary. If it’s not, all the more better. I don’t know what a contactor is or used for? And then, if it’s not necessary, I wouldn’t even know how the heck to override it and splice all the wires together.

Perhaps they had the contactor installed when the sweep booster pump was being used. Maybe to provide some sort of protection for the pool pump so that the pool pump has to run if the booster pumps on. I am just shooting blanks right now. I don’t know it’s function.
What I meant by the statement was that if you wanted to have a contactor on hand before you had someone pull the existing one to see what the coil voltage was, you could buy one of each. That way no matter which voltage it is you'd have one to replace it with.

The most likely reason to have the contactor is to take the load of the pump(s) off the switch because most switches aren't designed for heavy inductive loads, and starting/stopping a motor will ruin it in short order.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Thank you Hootz, and Bamba Rambler.

I went here to learn about them:

I didn’t know that it helps to take the full load off the circuit. If that is the case and so that I don’t shorten the life of either my pump or the circuit, then it seems more beneficial to keep a contactor there. Right?

here’s another picture. You’ll see the open box with the contactor, above it is a switch that is off which controls the booster pump, above that is mechanical timer that used to run the booster pump which is also off, in the middle you’ll find the subpanel. To the left of the sub panel is the mechanical timer for the pool pump which is left on without any timer stops, below that is a switch for the pool pump which is on. Directly below the right of sub panel is a switch for the light. And below the subpanel to the left is an outlet.


C41644B1-7840-429F-A74A-C71F084BF243.jpeg
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
When I inspect the wiring closely, there is a red wire coming from the top that connects to the top contactor corner left. There’s a black coming out of the top of that connects to the contactor top right. There is a red coming from the bottom that connects to the contactor bottom left. There’s a black coming out of the bottom that connects to the contactor bottom right. There is a pink that comes from the top that attaches in to the back of the contactor. And there is a pink coming from the top that connects in to the bottom of the contactor. There is a green wire coming from the top but doesn’t connect with the contactor.
 

bbrock

Well-known member
Apr 15, 2014
730
Livermore, CA
Here are a couple things I put in my Amazon cart. I chose these because it looks like they attachment mounts at the top and the bottom, they come as 30 amp 120 V and 30 amp 240 v. All of the breakers in my sub panel here are 20 amp so I don’t see how I actually need a 30 a.m. but this is the only design with attachment mounts at the top and bottom I could find.

Eaton C25DND330B Definite Purpose Contactor, 50mm, 3 Poles, Screw/Pressure Plate, Quick Connect Side By Side Terminals, 30A Current Rating, 2 Max HP Single Phase at 115V, 10 Max HP Three Phase at 230V, 15 Max HP Three Phase at 480V, 208-240VAC Coil Voltage Eaton C25DND330B Definite Purpose Contactor, 50mm, 3 Poles, Screw/Pressure Plate, Quick Connect Side By Side Terminals, 30A Current Rating, 2 Max HP Single Phase at 115V, 10 Max HP Three Phase at 230V, 15 Max HP Three Phase at 480V, 208-240VAC Coil Voltage: Motor Contactors: Amazon.com: Industrial & Scientific

Eaton C25DND330A Definite Purpose Contactor, 50mm, 3 Poles, Screw/Pressure Plate, Quick Connect Side By Side Terminals, 30A Current Rating, 2 Max HP Single Phase at 115V, 10 Max HP Three Phase at 230V, 15 Max HP Three Phase at 480V, 120VAC Coil Voltage Eaton C25DND330A Definite Purpose Contactor, 50mm, 3 Poles, Screw/Pressure Plate, Quick Connect Side By Side Terminals, 30A Current Rating, 2 Max HP Single Phase at 115V, 10 Max HP Three Phase at 230V, 15 Max HP Three Phase at 480V, 120VAC Coil Voltage: Motor Contactors: Amazon.com: Industrial & Scientific