Generac Load Shedding Devices - Shedding with no Applied Load!

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CastleEd

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Location
Renton, WA.
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Residential Electrical
Hello Everyone! first time post for me! I am stuck.
Ive been installing Generac load shed devices for 13+ years and have never come across this issue...under normal utility power, and with no loads being applied, expect for the little light indicators, the load shed devices are randomly shutting off the attached circuits. After sometime, again randomly the circuits are being re-engaged. No loads are being applied. All this is happening under utility power conditions not generator power.
I have three units installed (oven, dryer, speed oven). I thought I must have got a bad batch so I pulled them out and replaced them, still happens. Called the utility company to check incoming power variables, all good. I called Generac and they never even heard of such thing!
Anyone having similar issues? or any insights...Am I missing something right in from of my face?????
 
Perhaps there is some type of interference that's false triggering the circuitry inside of these devices that's used to detect a drop in the AC frequency (which would happen in a highly loaded generator).
Do you know if the utility uses smart meters with TWACS communication over the powerline? I've not heard of the problem that you're seeing, but I'm just throwing this out as something to consider.
 
??
Did the utility check the frequency also? I know that sounds dumb but it wouldn’t hurt to at least check that.

My understanding is the modules read the frequency on the E terminals. Perhaps something is miswired on the tabs beside the E terminals from the factory on the pre made panel?

edit. As synchro stated that’s something to check also. I’ve also discussed TWACS issues here before.

I know it seems random but keep up with the time it trips out and reconnects. Ask the utility their read times.
The utility may need to adjust the firing angle just a little.
 
synchro said:
Perhaps there is some type of interference that's false triggering the circuitry inside of these devices that's used to detect a drop in the AC frequency (which would happen in a highly loaded generator).
Do you know if the utility uses smart meters with TWACS communication over the powerline? I've not heard of the problem that you're seeing, but I'm just throwing this out as something to consider.
Click to expand...
Well, see, thats the silly thing about it...its triggering without the generator being on. Ive witnessed it with everyone in he house gone and watched the load shed just switch to disconnect the load. They do have the smart meters, but then again so do the rest of my customers here in the PNW. My other customers have not had this issue....
But I am with you that there must be some sort of interference being generated, or some random drop in the AC frequency...but how to isolate...
 
Hv&Lv said:
??
Did the utility check the frequency also? I know that sounds dumb but it wouldn’t hurt to at least check that.

My understanding is the modules read the frequency on the E terminals. Perhaps something is miswired on the tabs beside the E terminals from the factory on the pre made panel?

edit. As synchro stated that’s something to check also. I’ve also discussed TWACS issues here before.

I know it seems random but keep up with the time it trips out and reconnects. Ask the utility their read times.
The utility may need to adjust the firing angle just a little.
Click to expand...
I did request it but their unit for that was out for repairs.....
 
One reason I mentioned TWACS is that interference would be more likely to make a typical frequency detection circuit falsely indicate a higher than normal frequency vs. a lower one. But TWACS sends data using discrete jumps of phase modulation on the AC waveform, and so that might have more unpredictable effects.

CastleEd said:
They do have the smart meters, but then again so do the rest of my customers here in the PNW. My other customers have not had this issue....
Click to expand...

Perhaps the amplitude of TWACS signalling (assuming it exists) could be larger than normal on the distribution line for this customer, and that's causing the devices to "go over the edge" with false detections. Do you know if any of these customers without the problem are being fed by the same substation as this one? I believe TWACS modulation is typically applied at the substation level.
 
synchro said:
.



Perhaps the amplitude of TWACS signalling (assuming it exists) could be larger than normal on the distribution line for this customer, and that's causing the devices to "go over the edge" with false detections. Do you know if any of these customers without the problem are being fed by the same substation as this one? I believe TWACS modulation is typically applied at the substation level.
Click to expand...
It does exist, which is why I mentioned firing angle adjustment.
These modules generally shed at 60.5hz, so it could be counting the blip. But again, seeing as how the detection takes place at the E1 and/or E2 terminals one would think something would be crossed on the factory wiring.

TWACS is at the substation level. We have a TWACS XF at every sub specifically for that.
 
Don’t know how those are connected, Generac started using those after we quit installing them, but I would assume the module is powered off the generator output, unless it is powered off the generator battery, and just uses the generator output as an input. If it is powered by the battery, maybe the charger or battery is defective, not keeping sufficient voltage to the module? Without a wiring diagram, I’m just guessing at this point.
 
synchro said:
One reason I mentioned TWACS is that interference would be more likely to make a typical frequency detection circuit falsely indicate a higher than normal frequency vs. a lower one. But TWACS sends data using discrete jumps of phase modulation on the AC waveform, and so that might have more unpredictable effects.



Perhaps the amplitude of TWACS signalling (assuming it exists) could be larger than normal on the distribution line for this customer, and that's causing the devices to "go over the edge" with false detections. Do you know if any of these customers without the problem are being fed by the same substation as this one? I believe TWACS modulation is typically applied at the substation level.
Click to expand...
Synchro & HvLv, I think that may be it. This particular customer is "in the woods" and on a different utility company than we normally deal with. I'm thinking they may have to adjust the firing angle. I did some further research to back up the theory of the meter and EMF signal scrambling that is beginning to show itself in other areas. Thanks guys! great minds out there!
 
hillbilly1 said:
Didn’t find exactly the diagram I wanted, but did find there is a jumper to set for 50 or 60 hz. The instructions say to move the jumper to 50 hz if the area has bad utility power.
Click to expand...

I think it's saying to move the "Lock Out" jumper on the PC board to position B if there is unstable utility power. The 50/60Hz jumper is a different one. Without knowing exactly what that does, it's worth a try to see if position B works better.
 
synchro said:
I think it's saying to move the "Lock Out" jumper on the PC board to position B if there is unstable utility power. The 50/60Hz jumper is a different one. Without knowing exactly what that does, it's worth a try to see if position B works better.
Click to expand...
Your right, I just read the frequency jumper, and the next paragraph looked like it was part of it. My bad!
 
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