Lightning strike, well pump box failed

[WoodChuckDad]

Big storm last night. Around midnight last night, there was a bright flash and loud electric pop in the house the. Thunder half a second after. I got up and checked around. Lights were all working and no breakers thrown so I went back to bed. Wife woke me up in the morning to say we had no water. I checked the breaker, pressure switch and pump control box with a non contact voltage tester and showed voltage all the way to the pump line so I thought the pump was fried. But then I remembered the reset button on the control box and pushed it. The water came back on. Now I’m a hero.
A couple minute later my wife told me the bathroom didn’t have water.
Now I’m a zero. I pushed the reset button again and it worked for about a minute then Blew. I pressed it again and it lasted ten seconds and this time it wouldn’t reset. I went thru all the trouble shooting listed on the inside cover. Relay failed. And the start capaciter also appeared to be bad. I found a suitable replacement 50 miles away so I took the day off and went to get it. Had to rewire things because this one has a magnetic switch where the old one didnt.
The water is working again but, the last thing I did was check voltages since voltage to the pressure switch is supposed to be lower now.
Line voltage going to the control box is 246. It’s a 3 wire line to the pump. Red, black and yellow. Red and black together measure 375 volts when the pump is running.
Why? And how? Is this normal?

 

[Fuddyduddy1952]

Should be 240v, what does each leg read, yellow to red & yellow to black? Maybe lightning damaged the breaker going to well. It should be same there with pump running as at well house, if not then sounds like damaged wiring.

 

[dstig1]

Do you have a pump with a VFD controller on it? Regular ones are 240, 2-wire plus ground. If so regular voltage measurements are not going to be what you expect.

 

[WinterDeere]

I pushed the reset button again and it worked for about a minute then Blew. I pressed it again and it lasted ten seconds and this time it wouldn’t reset. I went thru all the trouble shooting listed on the inside cover. Relay failed. And the start capaciter also appeared to be bad.

Given the inconvenience of being without water is huge, I'd be just slapping a new controller in place, and worry about debugging this one to keep as a backup. I'd hate to see you waste a few days playing with this controller, just to find out it's a bad pump, delaying the ultimate fix even longer.

That said, here's some info that can help you with debugging the controller, should you want to go that route:

Non-VFD well pump controllers are just simple motor starters, a start capacitor and a relay to switch it in/out of the circuit.

Your pump has three wires, one of which is the run winding, one is the start winding, and the third is the common leg between the two. The run winding of a single-phase motor (your well pump) is like a single-cylinder engine, or a bicycle with only one pedal. It runs fine once you get that flywheel or crank turning, but it's basically impossible to start the thing when it's been stopped at bottom-dead center.

The start winding provides the second pedal or cylinder, clocked off the first by 90 degrees, this clocking angle is controlled by the size of the start capacitor and the difference in resistance of the smaller wire used in the start winding. But it's not made to be left switched on all the time, and failing to disengage it can cause the symptom you're seeing... a tripped thermal switch or breaker.

Assuming the usual/simple configuration of a "cap start induction run" motor with a single starting capacitor and no run capacitor, a bad capacitor usually yields a motor that just won't start. When you apply power to it, it will just sit and hum, until it trips the thermal switch or breaker.

Usually, a thermal trip occuring after the motor is spinning points at either a bad motor or bad relay, not a bad capacitor. The bad relay can cause this by keeping the start winding engaged longer than intended, causing higher than normal current draw. Because the relay is infinitely easier to replace than the pump motor, swapping it out is the quicker of two options for debugging the problem, for most folks.

I suppose it is possible that a bad start cap could cause the motor to never reach near enough to syncrhonous speed to disengage the relay, but I've never seen that myself. More importantly, a new pump controller comes with both components, and will be the quickest way to either get back up and running, or discover you need a new pump.

 

[dbritt]

Big storm last night. Around midnight last night, there was a bright flash and loud electric pop in the house the. Thunder half a second after. I got up and checked around. Lights were all working and no breakers thrown so I went back to bed. Wife woke me up in the morning to say we had no water. I checked the breaker, pressure switch and pump control box with a non contact voltage tester and showed voltage all the way to the pump line so I thought the pump was fried. But then I remembered the reset button on the control box and pushed it. The water came back on. Now I’m a hero.
A couple minute later my wife told me the bathroom didn’t have water.
Now I’m a zero. I pushed the reset button again and it worked for about a minute then Blew. I pressed it again and it lasted ten seconds and this time it wouldn’t reset. I went thru all the trouble shooting listed on the inside cover. Relay failed. And the start capaciter also appeared to be bad. I found a suitable replacement 50 miles away so I took the day off and went to get it. Had to rewire things because this one has a magnetic switch where the old one didnt.
The water is working again but, the last thing I did was check voltages since voltage to the pressure switch is supposed to be lower now.
Line voltage going to the control box is 246. It’s a 3 wire line to the pump. Red, black and yellow. Red and black together measure 375 volts when the pump is running.
Why? And how? Is this normal?

If you have an ohm meter, unhook the wires to your well (shut off the breaker first!) and check each one individually to ground. If you have any reading on any wire, the pump motor is probably bad. It will draw excessive current and cause the breaker to blow even though it worked for a few minutes. But, even if the pump motor is bad, there's no way you can have more than 250 volts on the pump side. That's the voltage being supplied by your electric company. To have more than that you would have to have 3-phase service, in which case you could have over 400 volts between come of the wires. If you don't have 3-phase power, then either you are reading the meter wrong or you have a Variable Frequency Drive control box. A VFD may have higher voltage on the pump side because it's basically a single-phase to 3-phase converter. I had a VFD controller at my poultry farm and loved the constant steady pressure it provided. BUT, when it went bad, it was VERY expensive to replace it. I think today they are around $5000 just for the control box. Sounds like you may need to call a well guy and let him figure it out. If it's a bad motor you are going to have to get him to pull the pump anyway. Good luck.

 

[WoodChuckDad]

I didn’t replace any components.
I replaced the entire box. This is a brand new Goulds xylem brand control box that I bought yesterday as replacement. The control box is 1 1/2 hp, 1Ph, 60hz, 230v MC control box
My power is single phase.
It replaced a similar franklin electric control box, but this one has the magnetic control switch. Previously I had it wired with 240 v to pressure switch and then to control box. Then to pump.
This “deluxe” box is wired 240 to the control box with a switch wire and an L 2 wire to the pressure switch. The three wires for the pump come off the control box.
L1 and L2 going from breaker to control box read 246. The power coming off the control box going to the pump was reading 375. I will check each leg coming off breaker individually later today. (I’m laying in bed awake at 430).
I will also run ohm check on the legs of the pump wire.
Old box. View attachment IMG_5257.jpg


New boxView attachment IMG_5260.jpg

 

[WoodChuckDad]

Also I do not have a VFD. This box was $275.
I do have a csv cycle stop valve in the line from pump to surface.

 

[steve tym]

That control box and motor are "capacitor run". I.E. the auxilary winding (red wire/start winding) is energized even after the motor starts.
The magnetic switch means there is now no load at the pressure switch, it just energizes the magnetic switch. Better. I'm perplexed that you have high voltage on the red wire, but the capacitor could be upping the voltage. Not sure I've ever checked voltage there.
If you can get your hands on an amp meter, yellow should be about 11.5 amps, black about 11 amps and red about 1.3 amps.

 

[Valveman]

The lightning was just a coincidence. The pump tripped the overload because the start cap was bad. The start cap and relay are not even in the circuit after the pump is started or when the pump is off. So, lightning does not take out start caps and relay. Lightning will blow a hole in the side of of the motor or blow the wires into, but not make the start cap fail. The high voltage after the control box is from the running capacitor, which is common on 1.5HP or larger.

I knew you did not have a VFD because if you had even heard thunder from afar, the VFD would have failed. There is no overload to reset on a VFD. When they get hit or just quit a new VFD controller is needed for $1200 to $5K, which is exactly why pump companies push VFD's.

VFD controls require frequent and costly replacements. Pumps without a CSV cycle themselves to death. A failed start cap, pressure switch, tank diaphragm, or check valve is a sign the pump is cycling on and off too much and will have a short life. Pumps controlled by a Cycle Stop Valve last for decades without any maintenance, which is exactly why pump companies try there best to talk you out of one.

 

[WinterDeere]

But, even if the pump motor is bad, there's no way you can have more than 250 volts on the pump side. That's the voltage being supplied by your electric company. To have more than that you would have to have 3-phase service, in which case you could have over 400 volts between come of the wires.

There are a few things can cause one to measure much higher than 240 volts, on a 240Vrms motor circuit:

1. Bad meter, obviously.
2. Max Hold or Peak Hold function on a DC meter, capturing waveform maxima or transient peak.
3. Measuring DC voltage with capacitor in circuit. Remember the "240 volts" we call out is the RMS value, by convention, created by a 340 volt amplitude waveform.
4. Measuring DC voltage on starting leg, shortly after it's been switched out of the circuit. Large transients happen due to inductive kick from the motor, which can charge the capacitor up even higher than 340 volts.

Scenario 3 is very unlikely, as the motor impedance is low, and should be constantly dragging the cap voltage back down. But scenario 4 is very possible, and seems likely if OP is measuring 375 volts. This is why you will see OEM motor start capacitors are always rated at least 1.4x higher than line voltage, and one big reason they fail when replaced with a lower voltage substitute by people who don't understand.