SCE (S Cal) My Line Voltage Sucks!

[Git]

My system has been up and running for just about 2 weeks now and I never realized how bad the voltage is from Southern California Edison until my SolarEdge Inverter went offline about a week ago

I am really amazed at all the data I can access through the SolarEdge monitoring system using their string inverter and optimizers. The voltage started out around 7 am at an indicated 232 volts before climbing slightly, and as power demand in the area increase, the voltage slowly decreased and gets as low as 209 before tripping the inverter and taking it off line. The inverter threw a couple of error codes -> AC Voltage Too Low and Phase Balance Error"

Now I am waiting to SCE to come out and check things out - it may take as long as 5 days. But as I write this post at 2:30 PM, I just physically checked the voltage at the main panel (line to line) and it is at 219

The inverter is set to trip at 211

[silversaver]

The voltage drop is pretty normal depends on usage in your area. You probably better off to have the installer re-program the operation range to avoid shut off of inverter. Waiting for SCE to boots up the voltage is most likely not going to happen. Most of the inverter manufacture set voltage from 211V to 264V, but that can be re-program.

[FFE]

Wow. My voltage is usually between 230-245. It is 236 right now (3:26 pm). My average is 237. SCE seems to keep it pretty high here which helps minimize my clipping.

[Git]

Wow. My voltage is usually between 230-245. It is 236 right now (3:26 pm). My average is 237. SCE seems to keep it pretty high here which helps minimize my clipping.

I would tend to agree with you. Having voltages that drop over 12% can't be good - but I have sent an email to SCE asking what there tolerances are.

To ask my installer to deliberately go into my inverter and change the high and low limits is ludicrous in my opinion. They have those limits set for a reason. I guess under the same type of logic, if your constantly tripping a 15 amp circuit breaker - just pop in a 20 amp?

[bcroe]

If you want to run, you have 3 choices. Get the PoCo to fix their voltage (while you wait indefinitely losing your investment), add a big auto
transfomer to adjust it yourself, or reprogram the inverter slightly to better match the line. There might be both a line voltage (240V) and a line to
neutral (120V) monitor needing adjustment.

It isn't the same as just upping a breaker (beyond the wiring capacity). You don't set the line V, the PoCo does. The limits were set to avoid
something really extreme, but were a bit tight for sloppy PoCo operation slipping outside their requirements. Bruce Roe

[Git]

If you want to run, you have 3 choices. Get the PoCo to fix their voltage (while you wait indefinitely losing your investment), add a big auto
transfomer to adjust it yourself, or reprogram the inverter slightly to better match the line. There might be both a line voltage (240V) and a line to
neutral (120V) monitor needing adjustment.

It isn't the same as just upping a breaker (beyond the wiring capacity). You don't set the line V, the PoCo does. The limits were set to avoid
something really extreme, but were a bit tight for sloppy PoCo operation slipping outside their requirements. Bruce Roe

Not sure what you are talking about....
What investment am I losing?
Who said that the customer sets the line voltage? (I didn't) That was the whole point of this post was to alert other users that there line voltage may be extremely low which can cause problems with their equipment

I imagine that SCE will respond, look into it and take appropriate action. Otherwise, that is what the Public Utilities Commision is for

http://www.cpuc.ca.gov/contactus/

[SunEagle]

If you want to run, you have 3 choices. Get the PoCo to fix their voltage (while you wait indefinitely losing your investment), add a big auto
transfomer to adjust it yourself, or reprogram the inverter slightly to better match the line. There might be both a line voltage (240V) and a line to
neutral (120V) monitor needing adjustment.

It isn't the same as just upping a breaker (beyond the wiring capacity). You don't set the line V, the PoCo does. The limits were set to avoid
something really extreme, but were a bit tight for sloppy PoCo operation slipping outside their requirements. Bruce Roe

I agree. Sometimes being on the end of a feeder a customers voltage will swing with the load. The POCO has to keep switching capacitor banks on and off to regulate the voltage to stay within "spec". But that range sometimes goes outside a solar inverters.

Using an auto-transformer can help regulate what the inverter sees to keep it happy. Or you can use a slightly higher cost transformer that regulates the output voltage to be maintained to +/- X %. The tighter the % the higher the cost.

Sola is one company that make those types of transformers. They are used for computer or critical power systems where the output is regulated to +/- 1% as well as filtering out all types of harmonics and transients. My company also makes those types of transformers but that is another story.

[bcroe]

What investment am I losing?
Who said that the customer sets the line voltage? (I didn't) That was the whole point of this post was to alert other users that
there line voltage may be extremely low which can cause problems with their equipment

I imagine that SCE will respond, look into it and take appropriate action. Otherwise, that is what the Public Utilities Commision is for
http://www.cpuc.ca.gov/contactus/

Your investment is your equipment, which is doing nothing when the PoCo won't let it run.

The voltage limits programmed into the inverter are supposed to work, if the PoCo does their part. Having the limits implies
you could put very bad voltages on the line without them, but you can't.

Your own voltage regulating transformer sounds like a magic bullet. But at 60 Hz it would be quite large and expensive, and
would probably exhibit a much higher impedance than a direct line connection, possible tripping the inverter anti islanding
monitor. An auto transformer might be used to shift the line just a few volts to get in range most of the time. So only the
DIFFERENCE in voltage is handled by it, it would be maybe 1/20 the size. And with most of the power flowing straight
through, the anti islanding monitor would probably be happy. HOWEVER, the whole transformer idea, working in theory,
is probably beyond what could practically be done by most. Bruce Roe

[solarix]

I've more often seen problems with the line voltage being too high which is aggravated by solar inverters lifting it up a bit more. In fact on installs where the inverter is a long ways (opposite end of the house), we've started to oversize the AC wire run to minimize future problems with too much voltage drop adding to the utility voltage.
Inverters are listed by UL for operation within a certain voltage range and you have to get formal permission from your PoCo and the manufacturer before altering your inverter's internal settings. The inverter is made to have these adjustments but it can be a hassle getting the permissions.

[bcroe]

The inverter is made to have these adjustments

If that is true, there is no need for the mfrs permission. With a grid tie agreement, the PoCo has ALREADY given permission
to operate in their "normal" condition.

[Git]

Update - SCE rolled a truck out on Sunday afternoon and acknowledged there is a problem at the local sub station. Yesterday I saw an improvement and today as of 3 PM we were actually at 239 and even hit 240v for a couple of hours. Kudos to SCE so far for dealing with it in a timely manner