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Discussion Starter · #1 ·
I put in a circuit for a couple of sump pumps today. The nameplate rating on each of the sump pumps was approx. 9.5 amps. (I know it was 9.something.) I put both on a single 20A circuit. I am probably overthinking this, but I am wondering what the chance is of both of them starting at the same time and tripping the circuit breaker. I really don't know how much current these motors will actually draw at start up.. Hmmm... any thoughts?
 

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Considering they will have a start current of approx. 57A. each, should have considered two circuits. How far from the panel are they?
 

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I put in a circuit for a couple of sump pumps today. The nameplate rating on each of the sump pumps was approx. 9.5 amps. (I know it was 9.something.) I put both on a single 20A circuit. I am probably overthinking this, but I am wondering what the chance is of both of them starting at the same time and tripping the circuit breaker. I really don't know how much current these motors will actually draw at start up.. Hmmm... any thoughts?
You probably have a violation of 430.24 unless you lock out one motor from the other one to prevent a simultaneous operation of both at the same time.
What size wire did you use for your 20 amp circuit?

And then there is 430.53 for you to look at.
 
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Discussion Starter · #5 ·
You probably have a violation of 430.24 unless you lock out one motor from the other one to prevent a simultaneous operation of both at the same time.
What size wire did you use for your 20 amp circuit?

And then there is 430.53 for you to look at.
I'm looking now... 12 AWG
 

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Discussion Starter · #6 ·
You probably have a violation of 430.24 unless you lock out one motor from the other one to prevent a simultaneous operation of both at the same time.
What size wire did you use for your 20 amp circuit?

And then there is 430.53 for you to look at.
As best as I can tell, I am in violation of 430.24 because of the size of the conductor. As for assurance of having a reliable system, I think it's best to have two circuits. I told the customer today that I might have to install another circuit. It looks like I am going to have to give her a call tomorrow. Thanks for pointing me in the right direction.
 

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Old Grumpy Bastard
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As best as I can tell, I am in violation of 430.24 because of the size of the conductor. As for assurance of having a reliable system, I think it's best to have two circuits. I told the customer today that I might have to install another circuit. It looks like I am going to have to give her a call tomorrow. Thanks for pointing me in the right direction.
I wouldn't have even tried to put them both on the same circuit.
 

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I see you've already decided to do two circuits but even code aside, these are sump pumps, a blow breaker probably means a flood / mess, you'd probably want two circuits just for reliability / redundancy.
 

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I agree with the guys above and with two sump pumps it best to run it own circuits as they stated the reason why.,

the other reason why I rather keep it on it own circuit for each pump in case one fail due motor kicked out or something along the circuit get overloaded and kick out and can created a mess there.

And also I am not too suprised some people will upgrade the size of sump pump motor to the larger one that pretty much seal the deal.

You should ask the customer a sump pump alarm in there as well in case both actually quit.

I would have one sump pump on Alpha phase and second on on Bravo phase ( leg )
 

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We do quite a few sump pump installs with all the ag work we do.

I've settled on purchasing strictly Alderon sump controllers from Western Hydro up in Tri-Cities, WA.

I usually come up with how many circuits to run based on the motor FLA and what is going to happen if the pumps quit working or trip their breakers. The Alderon's I buy can be set up with up to three circuits for duplex pumps. One circuit for each of the pumps plus a separate control circuit if desired.

At a minimum this would of had two circuits ran to it just based on the FLA, unless only one pump can run at a time. If it was important the alarm functioned because of an issue, we would of ran 3 circuits.
 

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Discussion Starter · #12 ·
I see you've already decided to do two circuits but even code aside, these are sump pumps, a blow breaker probably means a flood / mess, you'd probably want two circuits just for reliability / redundancy.
I agree. - I was trying to save the customer some money... I'm just glad I told her that I might have to do it anyway. I called her and she thanked me; I plan to charge her the difference and she seemed okay with that. Lesson learned.
 

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Discussion Starter · #13 ·
I agree with the guys above and with two sump pumps it best to run it own circuits as they stated the reason why.,

the other reason why I rather keep it on it own circuit for each pump in case one fail due motor kicked out or something along the circuit get overloaded and kick out and can created a mess there.

And also I am not too suprised some people will upgrade the size of sump pump motor to the larger one that pretty much seal the deal.

You should ask the customer a sump pump alarm in there as well in case both actually quit.

I would have one sump pump on Alpha phase and second on on Bravo phase ( leg )
I'd say you are right on all points. I like your thinking and I appreciate your input. Any suggestions on an alarm? I have never done that, but I do like the idea. These are just small sump pumps under a crawl space.
 

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Discussion Starter · #15 ·
The 9 or so amps you quote in post 1
is that the running current, start current or FLA ?

:glasses:
Honestly, I am not really sure. - The pumps were both in place and the plates were very hard to read. Again, these were located in a crawl space and both were sitting in water. I was able to make out 9.5 amps on the plate and, if I remember correctly, they said 1/2 HP... (something like that.) I'll be going there again this Saturday, or before, and I'll try and get a better look.
 

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Old Grumpy Bastard
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Thank you for your valuable input.
1. You have 2 motors they say they require 9+ amps to run.

2. You know they will draw more than that on start up.

3. They could possibly start at the same time.

What part of that sounds like a 20 amp circuit would be fine?
 

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Just wondering since you got if that you need two circuits. Were the pumps already there and how were they working before. Or are they new and cust. installed and now needs power to them. I don't know about your area is it prone to flooding cause I have never seen a pump let alone two in a crawl space. Assuming this is a home it sounds like some landscaping was done and the grade was changed causing water to enter crawlspace. Lastly is there a dust cap of concrete or is it dirt and plastic, if so the pumps should be in a sump box or something to keep dirt and debris out. You mentioned something about 1/2 HP or something that is a big pump. Why so much water? Just curious cause nothing to add electrically, it was all covered.
 

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Discussion Starter · #18 · (Edited)
1. You have 2 motors they say they require 9+ amps to run.

2. You know they will draw more than that on start up.

3. They could possibly start at the same time.

What part of that sounds like a 20 amp circuit would be fine?
Do you happen to know what amount of current will cause a GE inverse time circuit breaker to trip instantaneously? Do you know how long those particular motors produce their particular amount of startup current, or even if they do produce the amount of current required to throw the breaker? I don't. I do suppose this information might be obtained but I failed to do so... Alas, I probably should have erred on the side of caution rather than economy. The problem is now fixed.
 

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Discussion Starter · #19 ·
Just wondering since you got if that you need two circuits. Were the pumps already there and how were they working before. Or are they new and cust. installed and now needs power to them. I don't know about your area is it prone to flooding cause I have never seen a pump let alone two in a crawl space. Assuming this is a home it sounds like some landscaping was done and the grade was changed causing water to enter crawlspace. Lastly is there a dust cap of concrete or is it dirt and plastic, if so the pumps should be in a sump box or something to keep dirt and debris out. You mentioned something about 1/2 HP or something that is a big pump. Why so much water? Just curious cause nothing to add electrically, it was all covered.
It's dirt, and mud... lots of it. And, water. (Ugh.) The pumps were recently put in by another contractor. They are indeed as you described, (in a little sump box; two separate boxes in different areas.) They were plugged in using extension cords. (I didn't pay attention to where the cords were plugged in. - In fact, I left the cords right where I found them.) They will be putting plastic down at a later date. The contractor doing that work wanted the pumps plugged into permanent power first. I'm not sure what gives with all the water, but I got my boots pretty muddy just walking to my van and back... My feet were sinking in their front lawn, making deep prints. The owner just said it's always been that way. I'm pretty sure the property isn't located in a hole; in fact it seems that they are on a hill. (It's a higher part of the city.) However, it might be due to the grade surrounding the home as you suggested. I've seen plenty of sump pumps in crawl spaces around here, but this is the first time I have seen two. - In fact, the crawl was more wet this evening when I went back to add another circuit than it was when I was there the first time. The pumps were still powered and the circuit was still on... But, somehow, it seems that a lot of water is just draining onto their property.
 

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Do you happen to know what amount of current will cause a GE inverse time circuit breaker to trip instantaneously? Do you know how long those particular motors produce their particular amount of startup current, or even if they do produce the amount of current required to throw the breaker? I don't. I do suppose this information might be obtained but I failed to do so... Alas, I probably should have erred on the side of caution rather than the economy. The problem is now fixed.
20 amp CB 120-240 amps (6-12 times)

Sump pump depending on several factors 4-14 times.

4x9 ampsx2= 72 amps
14x9 ampsx2=252 amps

Shake the dice and see how it rolls out or install 2 circuits. It is your reputation on the line.
 
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