Where Shall we Meet for Coffee on Sunday?

[Twisted_Twin]

Did you find out what caused it?

[Kiwi_Roy]

I have never been a fan of those jumpers, I always like to see short jumper wires between each terminal daisy chain fashion.
One thing though it tells you how well there terminals are desighned not to cause a fire even though red hot.

[Kiwi_Roy]

Oops

[Kiwi Canuck]

Did you find out what caused it?

I did not determine the cause, but suspect tree roots had made their way into the sump and one of the pumps got the roots caught in the intake causing an overload situation, coupled with loose connectors on the neutral wires in the terminal strip it started arcing, causing the melted terminals.

The terminals I installed are rated at 30 Amps and I tightened them well, so hopefully we will be safe.

Roy, I love those bridging clips, saves a lot of finicky work with jumpers and it makes it nice and tidy.

We use them at work and I have them on my mill and lathe as well, so no issues with them so far.



David

[Kiwi_Roy]

David,
         No doubt you install those jumpers properly, you can see what happens if they aren't
Wire jumpers should never work loose like that, that's my preference, they are just as neat, we don't loom the terminal strips any more.

On a long terminal strip I insist on looping both ends back to the source so as well as the extra security it allows you to work on the system without taking a shutdown.

[Kiwi_Roy]

The circuit breaker on your pumps has a rating of 10,000 Amps, even if your jumpers are done up tight there's a chance they might fail again, the inrush current could be in excess of 100 Amps, I can lend you a clip if you don't have one
Or if you have the motor nameplate you could look it up
I strongly suggest you change that wiring. These jumpers are ok for controls and wires not carrying much current but this is the neutrals carrying the heavy starting current, even if you jumper a piece of No 16 in the empty spots at the top.

[Kiwi Canuck]

The circuit breaker on your pumps has a rating of 10,000 Amps, even if your jumpers are done up tight there's a chance they might fail again, the inrush current could be in excess of 100 Amps, I can lend you a clip if you don't have one
Or if you have the motor nameplate you could look it up
I strongly suggest you change that wiring. These jumpers are ok for controls and wires not carrying much current but this is the neutrals carrying the heavy starting current, even if you jumper a piece of No 16 in the empty spots at the top.

Thanks for the input Roy, I'll put a jumper on the spare neutral terminals as you suggested.

The pumps are rated at 10 amps (1/3HP) each, but I'm not sure on the inrush.

The pumps are made by Hydromatic and they are model SW33A1, manual just shows total current as 10 Amps.

I'll give you a call to discuss further.

David

[fffCycles]

By NEMA if the motor does not state "low-inrush" you may assume any where between 5 and 8 times FLA as typical inrush so I always go for worst case. It is true some motors will have higher momentary currents depending on impedance and phase angle on closing but ten times would be a max figure I would reckon. I prefer the comb type jumpers that Phoenix used to use but even then it was only as good as the person tightening the terminals.

Frank

[Kiwi Canuck]

To sum up what I've found on the sump pump issue since the terminal strip had a melt down.

I have (2) identical 1/3 HP sump pumps controlled by a Duplex Sump Controller, the pumps are rated at 10 Amps, based on the name plate.



I used my clamp meter this morning and discovered that Pump # 1 is drawing approx. 12.6 Amps while running and Pump #2 draws 8.3 Amps while running.

Something has caused the # 1 to draw 50% more power than it should and may have contributed to the overloaded circuit which caused the arcing in the terminal strip.

I have shut off the affected pump and have determined that one pump can manage the water level adequately for now.

Hopefully I can find the same unit to replace it or something very close, it uses a remote float system, not one tethered to the pump.

Now I just need to find a way to remove the burnt electrical smell from the basement, I tried my Ozone generator but it didn't seem to make any difference, I guess burnt plastic insulation isn't an organic compound.

David.

[Bucko]

A voltage drop (from ideal) will cause the current to increase in an AC motor - you may have some poor connections somewhere in the pump end of the circuit.

[Jodea]

How about Lelams tomorrow morning for coffee.

[Galactica]

How about Lelams tomorrow morning for coffee.

Sure.

[Kiwi_Roy]

Sounds Good

[Kurt]

Should we Porter's for coffee. It is sort of on the way for any Motorcycle Show people.

[Steve G.]

   I've got a couple errands early Sunday, before show, I'll miss coffee.