230V pump motor with 120V receptacle

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An existing spa has a 230V 1HP circulation pump on a 2 pole 20A breaker. The pool company we do service work for has added 120V cord and plug connected chemical feeder pumps to add chemicals into the spa. These feeder pumps cannot run when the circ pump is off. I know that a 230V contactor is an option, but why can't I pigtail off one of the lines of the 2 pole breaker, add a neutral and wire the receptacle. It sounds simple to me, but I can't help thinking I'm breaking a rule. The pump and the sub panel that feeds it are located in a vacpack (factory assembly consisting of a fiberglass enclosure housing the subpanel, pumps, light transformers, and other accessory items relating to pool functions). The receptacle would be installed directly from the subpanel.
 

Dennis Alwon

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You might be able to as long as you calculate the load for the two motors and they are protected properly.

If you add the load of both pumps and they don't exceed 125% of the circuit then you may be okay as long as there is overload protection in the added motor.
 
Thanks for the reply.

The loads are not an issue. The 1HP motor draws about 7A, and the feeder pumps are protected in their assembly by a 3A Buss fuse. I was thinking there may be a problem with a branch circuit supplying a 230V motor load as well as a 120V receptacle load.
 

dicklaxt

Senior Member
If you tap the line side of the braker what are you going to protect the wire to the motor with?

dick
 

dicklaxt

Senior Member
You might be able to as long as you calculate the load for the two motors and they are protected properly.

If you add the load of both pumps and they don't exceed 125% of the circuit then you may be okay as long as there is overload protection in the added motor.


You got it,just make sure the feed pump is interlocked down/off with the circ pump.

dick
 
You got it,just make sure the feed pump is interlocked down/off with the circ pump.

dick

What do you mean by "interlocked"?

The only way the pump will turn on or off is with the breaker. There is no timer or other switch. If I've tapped one of the lines off the breaker and added a neutral for the recep, then what else will I need to do?
 

Dennis Alwon

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Location
Chapel Hill, NC
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What do you mean by "interlocked"?

The only way the pump will turn on or off is with the breaker. There is no timer or other switch. If I've tapped one of the lines off the breaker and added a neutral for the recep, then what else will I need to do?
I think Dick was saying you don't want one pump to run without the other so you should make sure that does not happen.

If one pump failed then the other pump would still be running. If this does not affect anything else then I don't see why that would be an issue.
 
Gotcha. I don't think this is an issue. It is simply for convenience. They just don't want someone to shut off the circ pump at the breaker and then leave the chemical feeders running. Now if I did have to interlock the feeder pump to the circ pump, what type of device would I use? I'm thinking some kind of current sensor tied to a relay feeding the recep for the feeder pump?
 

Dennis Alwon

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Location
Chapel Hill, NC
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Gotcha. I don't think this is an issue. It is simply for convenience. They just don't want someone to shut off the circ pump at the breaker and then leave the chemical feeders running. Now if I did have to interlock the feeder pump to the circ pump, what type of device would I use? I'm thinking some kind of current sensor tied to a relay feeding the recep for the feeder pump?
This is the point that Dick was making if the pump fails then the chemical feeder pump will keep running. It may be simpler to add a water flow switch. If the water does not circulate then the feeder pump wont run.
 

elohr46

Senior Member
Location
square one
Gotcha. I don't think this is an issue. It is simply for convenience. They just don't want someone to shut off the circ pump at the breaker and then leave the chemical feeders running. Now if I did have to interlock the feeder pump to the circ pump, what type of device would I use? I'm thinking some kind of current sensor tied to a relay feeding the recep for the feeder pump?

I think you have the correct economical solution. A current sensor with NO contacts controlling a 120v RIB relay with NO contacts that controls the recept. that the chem feed motor is plugged into.
 

vplank

Member
Electrical safety ignorance

Electrical safety ignorance

I'm new to the group and I'm trying to determine electrical safety related practices. I'm currently reviewing the NFPA 70E Handbook for electrical safety in the workplace and I'm trying to determine is PPE (linesman gloves) required for testing, troubleshooting or diagnostic work above 50V?

Thanks for your help.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I'm new to the group and I'm trying to determine electrical safety related practices. I'm currently reviewing the NFPA 70E Handbook for electrical safety in the workplace and I'm trying to determine is PPE (linesman gloves) required for testing, troubleshooting or diagnostic work above 50V?

Thanks for your help.
You should start a new thread with your question.:)
 

dicklaxt

Senior Member
You would not need a sensor,wire the relay coil in parallel with the circ pump, and interlock the feed pumps via NO contacts,hence when circ pump shuts down the relay deenergizes,opening the contacts and shutting down the feed pumps.
dick
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
You would not need a sensor,wire the relay coil in parallel with the circ pump, and interlock the feed pumps via NO contacts,hence when circ pump shuts down the relay deenergizes,opening the contacts and shutting down the feed pumps.
dick
I don't get it. If the motor just stops, but still has power, or goes out on overload, how would that stop the feed pump from running.
 

Dennis Alwon

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Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I click new posts to start a new thread, but I only see how to reply to current threads. Help?
Go to the top of this page. On the left, not quite at the top there is a folder that says MIke Holt's Forum (in blue). Click there, then choose what category you want the thread to be posted in and then click new question.
 
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