One of the Arrays shut down today at 12:50pm due to an AC Fault. When I found it I turned off the GT3.8 and waited for the front display to clear itself, then I turned it back on and it rebooted and started to work.

The only thing I did prior to it shutting down was spraying water on the backyard slab. I may have sprayed some water around the outlets in the backyard, thats about it.



04-28-2007 12:50:42 377.7 8.55 377.7 3237 3021 93.33 257.7 10725 103 60 6115 20398 ST:3 STS:0000 0000 0008 92fa FA:00

04-28-2007 12:51:14 472.4 0.25 600.0 118 ------0 ------0 259.4 10732 _99 60 3091 20436 ST:0 STS:0080 0080 0000 92fa FA:10

AC fault means the utility AC was out of UL1741 specs ....

Nominal VAC is in the 230-40 VAC range ..

If you look at your GT-View log, your VAC is very high @ 258 VAC .. I would bump up your data logging to 1 second .. you will need this data to get anyone remotely interested in this issue ...

The lastest UL1741 spec's high trip @ 261 I believe ... You need to have your installer find out if

1) your wiring is OK, IE... not to small, if the inverters are producing energy, they will raise the VAC as they increase the energy back into the panel .. if the wiring, wether its from the inverters to the panel, or panel to the street to to small, it will allow the inverters to raise the voltage out of spec. Wiring should be at least 10 awg for EACH inverter, the mains should be 4 AUT

2) Could just be your utility is high VAC comming in, they will need to be called to adjust your tap. Wth the inverters offline, measure the VAC

3) If #1 is ok and #2 they don't respond, Xantrex does have a programming tool to site adjust the UL1741 trips ... you have to contact Xantrex to work thru this path. UL1741 is changing yearly, the high trip was 264 vac, but UL changed it, with the allowance for site specific adjustements when and where needed ... royal pain IHMO


Just to be clear, the inverter is functioning correctly and is going offline because the VAC is OUTSIDE UL1741 values.

Thank you very much, I totally understand where you are coming from, I will bump the Data Logging to 1 sec and will keep an eye out on the VAC, if it gets worst then I will first contact Xantrex to get the new firm ware to push the VAC limits to 261.

Thanks


Fred

Fred,

Your issue is probably not the Inverter programming or even the UL limits...

It is either your utility feed and/or your house wiring.

What you need to do is measure your utility voltage with and without the GT running.

If I understand your log correctly--your line voltage was 258 volts a little time before the GT tripped and 259 volts AC after your GT tripped (I think)...

My own home's utility power is about 238 VAC in the evenings and 240 VAC during the day (using the GT's LCD display)...

My guess is that you should only see a couple of volts change at most (ideally) if you check the voltage with the inverter running, then kill it's power and measure it with the inverter shut down. And you should be much closer to the 220-240 VAC range. 260 VAC is too high.

Also, you may need to check this with a known good DVM and make sure that the GT is correctly reading the input voltage.

There is always a small possibility that the GT hardware is measuring 260 VAC but the line is really at 240 VAC (I don't know the GT's internal design to know if this is even a possibility--but checking with a calibrated/known good DVM would help you to diagnose the problem).

-Bill

Using a Fluke-77, I checked 256 with the inverters online and 255 with the inverters offline. Looks like the feed is coming in too high. I will contact my staller and see if they can call SDG&E with a solution.

The input reading that the GT Displays shows is the same reading I got also.

Fred

Yah, thats way to high, you should be 240 nomial ...

The fact it's only one volt difference between on/off is good as well, means you have nice fat and well connected wires

You need the utility to come and check it out, you can call direct, as they LIKE when you call telling them the line is high, they want to fix it before things start blowing up and they have to pay for repairs. Call the repair line and tel them the line is to high, your data logging it and you need it fixed ASAP.

I had this at my other house, at first they were like, yah whatever ( but sent a crew on a Sunday anyways ), when they measured at the pole, he freaked and got on the phone, two hours later was fixed, a regulator at a substation had failed ... But this is also when Lakeland Electric found out about my First system ... thats another story

I sent 2 emails to my Installer so they are aware of the high VAC, I will contact SDG&E today or tomorrow as I don't think they would come out on a Sunday. SDG&E is pretty good about answering trouble calls.

Great info guys !!! you guys rock. Thanks alot for helpping me out.

Update: SDG&E will be coming out today to check it out.


Fred

Just a note, I split the topic as so other would have an eary way to search/resolve this type of issue

SDG&E came out at 1:12pm and said not only you but everyone in this area is too high. I was the only one to report it to them, he said it will be corrected Monday, he is submitting the work order to the engineers as we speak.

Only took him 1 minute to check or read the voltage.


Fred

I bet it will be corrected in an hour or two ... Electric Companys gets very nervous when the grid is NOT where they expect it to be. If someones refrigerator dies AND they know the line is high the Electric company can be on the hook, which means $$$, which means it will be fixed faster than just about any other service call ..

At least in your case you don't have to explain what the solar system is and why is it connected to the grid