nrp3
11 kW Evo unit. 16 circuit switch. Only load of significance is the well pump. Mostly lighting, boiler, couple of fridges. Not a whole lot. Balanced within 3 amps. Tech support concerned with well. Run at 10 amps, inrush shown to be at 42 amps. Tested with fluke clamp. History from early on of faulting out during utility loss. By the time I get there, unable to duplicate. Been through the usual tests. Latest software. Voltage shown on display and measured at breaker only 3 volts difference. Tried to make it fail for four hours today and nothing to show. I've load banked it before and it happily will carry the load. Gas pressures are fine (LP). Only happens during outages. Exercise is good weekly. Both customer and I are aren't too thrilled. Not my install, but can't see anything wrong with it either.
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Peddler
So sometimes the undervoltage is a false flag in that that just happens to be where the brain is as it scrolls through the faults as it is dying for other reasons. I just today had a unit that faulted on undervoltage but the output was fine. When I talked to the customer I found that the power had been on and off with only a few seconds in between several times. The generator had started and stopped a couple times and then faulted. In this case I found the start delay set to 5 seconds, now I can't prove it but I have solved a lot of problems I think by making this 10 seconds because it eliminates a lot of false starts. I then found the firmware to be an early version which may not have the multiple field flash upgrade. I surmised that after the unit started a couple times that it started so fast that it didn't catch the field flash the last time. Time will tell if these things fixed this unit but if everything else is good than you have to look outside the box sometimes. I would try to get as much info from the customer as possible as to the time and circumstances when it fails and think it through. Also double check all the controller plugs from the harnesses and make sure one isn't pushed back and not making contact all the time, I have seen this show an intermittent undervoltage fault before. Good Luck, we have all lived with units like this from time to time. Good Luck
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nrp3
I’ve updated software a couple of times. 1.17 was what was in there until I put in 1.20. It has always failed during an outage. Some ability to reproduce the problem by the customer, but I’ve never been able to get there and reproduce it. Initially it would happen about three hours into an outage, this last time it failed fairly quickly. New pressure tank on the well but older maybe original well pump. Might 10-15 years old. May not have anything to do with it. Was suggested that adding some load may reduce the amount of time it takes to react to the well coming on.
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Peddler
We don't sell the Evo unit so I don't know if there is something unusual about that unit. You need to be sure the normal load is not to high which could cause the in rush from the pump starting to pull the voltage down long enough to cause a fault. Depending on the well specs if it is more than a 1/2 Hp submersible pump the 11KW could be marginal.
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nrp3
Couple of quick outages of a minute or two and then the utility went out for about an hour. It ran normally for ten minutes before failing. By the time I got there, the power was back on and again couldn’t duplicate it, with or without the well pump running.
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MacL
I'd see about laying eyes or a mirror on the slip rings, and look very carefully to see if either or both has any grooves formed in them. After that I'd check the pins on wire 2,6, 11,44,4,0. Haven't had much problem with the grip on molex style connectors unless someone shoved a probe in one, have seen some grooved rings sometimes cause an undervoltage and other times not.
State your problem, not your diagnosis.
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nrp3
I spent a bunch of time looking for loose connections in the harness. The grooved slip ring idea is worth a shot.
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MacL
Actually the 2,6,11,44 wires in addition to the molex style where it plugs into the board there is another connector called STR (stator) connector. White, plastic 4 black wires plugging into 4 blue wires, that are fairly notorious for having a broken barb and backing out or being otherwise damaged within the connector. Look in the end with the black wires and make sure all the crimps are in line and one or more is not shifted out of the connector.
State your problem, not your diagnosis.
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nrp3
They had someone else look at it today and they got it to fail once with the pump, so my guess is that it has something to do with time. He told them it should run for four minutes before transferring. Looking at the log recently it ran nine minutes roughly, utility came back, it went out again twice in within less than a minute and failed 1902 the second utility loss, so I'm not sure I buy the long warm up to transfer. I'd have to look to see whether that is even something I can change. I know cold smart start is supposed to vary that time due to temp, but not sure we can modify this.
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