While investigating another issue I noticed the wire to my sump pump was hot and there was steam vapors coming from the well. Why didnt the fuse trip in this instance. The fuse panel in newish about 5 years ago. I had original panel replaced. The wire was very hot.
Why didnt this fuse trip
- Thread starter raaizin
- Start date
The sump pump has shorted to ground. But not enough "short" for the over current to trip the breaker. In electrical retraining the instructor had a plastic tub full of water. He had a hand held hair dryer. Turned it on and asked the class if they thought the breaker would trip. Every hand went up. He let go of the hair dryer. It just moved back and forth under the water. He had hooked up a Fluke meter to show voltage in the water. 0 before the dyer went in, 120 after it went in. Everybody learned that day. That's way you always need a GFCI outlet anywhere around water. I think it's 6' or closer. You local codes might be different.
Edit; Not a expert by any means here. Just repeating what I saw a instructor do in a class room setting. He had every degree you could get in electronics. He made everyone better because of how he taught.
Edit; Not a expert by any means here. Just repeating what I saw a instructor do in a class room setting. He had every degree you could get in electronics. He made everyone better because of how he taught.
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When I had this problem, it wasn't that the sump pump was shorted. It was because the float switch had failed in such a way that it wasn't supplying enough voltage to the pump to actually make it run, just enough to make it heat up the water.
The fix was a new float switch.
This problem did not blow a fuse or trip a breaker. It would not be expected to.
Which wire was very hot? The wire between the fuse panel and the outlet that sump pump is plugged into, or the cord between the sump pump and the outlet?
You may have a bad outlet causing a bad connection which is heating up the plug and the wire near it. Or maybe the plug itself is bad. Or both are bad, depending on how hot it got, it could damage both.
At work I once asked one of our plant electricians why the circuit breakers didn't trip before one of our big expensive pump motors completely burned out and almost caught fire before finally being disconnected. His short and sweet answer was that the circuit breakers are just there to protect the wiring. They don't care what the device is doing.
Your pump apparently wasn't overloading the circuit, especially if it is a 20A circuit. Most likely the pump motor has an internal thermal overload switch that kept everything from totally melting down, although overloads will cycle on and off and allow things to get quite warm.
Your pump apparently wasn't overloading the circuit, especially if it is a 20A circuit. Most likely the pump motor has an internal thermal overload switch that kept everything from totally melting down, although overloads will cycle on and off and allow things to get quite warm.
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The GFCI won't even trip because nothing is being lost to ground. Add a person in the mix with a path to ground and things will change.
The motor was laboring due to the pump seizing. The motor was pulling more current than it normally would but not 20 amps which would have blown the fuse. There was no short to ground or the fuse would have blown immediately.
Sump pumps, refridgerators and freezers, some other items should not have a GFCI as mentioned before. Having one is a recipe for a flooded basement or a bunch of spoiled food.
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Sump pumps should never have a GFCI unless you want a flooded basement. Spells it out in the electrical code book.
Code is to have all garage plugs to be GFI protected. Eventually everything even in the house will need it as well.
I humbly disagree with the GFI plugs in the garage for the reasons above. If it is a must, at least put a night light on the plug with the garage fridge or freezer.
If one plans on pressure washing their car in their garage, that is another story.
*My brothers new to him house has 6 plugs in the garage that weren’t working so he had me check it out. They’re GFI protected. Come to find out, the PO of the home put a huge cabinet in front of the GFI plug.
Anyways, an outdoor plug caused them to trip. We’ll try a new cover and some caulk on the top and sides of the cover. It’s in brick so it wasn’t sealing the best. I’m going to get rid of the GFI powering all the garage plugs and likely put it in the box just before the outside plug as I don’t think the small mason box will allow a chunky GFI.
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You cannot take his advice as “all breakers” though.” Yes breaker are sized for the load cables and do protect them. And in some instances that is its only purpose. However breakers can and do protect downstream equipment and are coordinated to do so. If you have an expensive motor or any expensive equipment then it should have a breaker or starter that is capable of protecting it. Someone decided to go cheap designing it or does not know how to properly coordinate it. Or maybe he just told you something to get you to leave him alone. But to say all breakers only care about cables is wrong.
Not enough info to troubleshoot this from just what you provided. Anything would just be a guess.
Breakers or fuses are best for a very quick, but high amperage surge, like a short would cause. Under a sustained load, they will may not trip even if you reached their rates amperage. You were probably around that edge.
I bet if you turned on another fixture or a device on that circuit it would’ve tripped.
I bet if you turned on another fixture or a device on that circuit it would’ve tripped.
I had a licensed electrician add a dedicated sump pump circuit in our unfinished basement. . He installed a GFCI. Electricians debate this all the time. Look it up - I'm no expert on this, so enlighten me, someone.
https://upgradedhome.com/does-a-sump-pump-need-gfci/
"Until about 2008, the NEC has a specific exception for sump pumps. Most sump pumps are installed in unfinished and finished basements. The exception provided that a sump pump did not need GFCI protection provided it was on a dedicated circuit with one outlet. This exception was removed
The latest 2020 edition of the NEC does not have this exception and has expanded the requirement for GFCI protection to include both finished and unfinished basements. Hence, the usual location of a sump pump in the basement would require a GFCI protected circuit."
https://www.electriciantalk.com/threads/sump-pump-gfci.295395/
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I wonder how many kids will now try this at home.
This. We had a swimming pool filter pump that the installer neglected to cover up, so water seeped in and corroded some spade connections. Pump ran fine until the corrosion caused a poor connection, which eventually caused the wires to burn, and finally one burned through completely. Breaker never tripped.
The other thing people don't realize is breakers have a time associated with them as well. So a 15A breaker will take a lot more than 15A for a very short time - milliseconds, before it will trip. You need to look up the curve for your particular breaker - if its published - another problem IMHO. That very short but very high current can easily be enough to fry electronics - which is why you need surge protectors.
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Don't mean to get off topic but,
My sump pump was sharing the line with other outlets.
Whenever the pump turned ON, my desk lamp would dim.
So, I added a new line and outlet and put the sump pump on a dedicated breaker (all for 20 amp).
I ended up using an GFCI outlet because the new sub-division down the street was putting them in at pump.
I also have a Night Light plugged into outlet so I can tell from a distance that outlet has power.
Hopefully one improvement I made was:
I added an ON/OFF switch that I can reach while standing on the basement stairs (hanging next to switch is an 'instruction card')
If there is ever water on the floor, I am now able to shut off the power to pump before standing in the water.
I also have a pair of Rubber Boots that I can reach while on the stairs.
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Actually...the code book requires a GFCI for sump pumps since at least the 2012 code.
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