APS having issues with line quality?

solar_dave
solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
I noticed lately more and more my Grid tie inverters are re-qualifying the line mid day. Generally when I see this happen the TED shows a large immediate shift in the line Voltage of 3-5 volts. I suspect the waveform gets a major distortion at the same time.

Do you think this is them bringing more generation capacity online?

Comments

  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: APS having issues with line quality?
    solar_dave wrote: »
    I noticed lately more and more my Grid tie inverters are re-qualifying the line mid day. Generally when I see this happen the TED shows a large immediate shift in the line Voltage of 3-5 volts. I suspect the waveform gets a major distortion at the same time.

    Do you think this is them bringing more generation capacity online?
    Could be that, or could be a tap changer for voltage regulation (especially if the voltage was at the end of a long decrease at the time of the change. When does it change back, or do you not see that?
    It could also be switching of a bank of power factor correction capacitors. Look at the harmonic content of the waveform before and after the change, since you cannot directly see the phasing effect.
    SMA SB 3000, old BP panels.
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: APS having issues with line quality?

    Yes looks like a voltage slide for 60 to 90 minutes or a consistent lower than normal voltage condition prior to the event. APS tends to run the Voltage here at 2-5 volts higher than the nominal 120V.

    The Yellow line is the Voltage the green line is the solar.

    Both times it triggered today the voltage headed sharply higher.
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: APS having issues with line quality?

    Just re-qualified again, about a 4 volt jump on the line again.
  • DanS26
    DanS26 Solar Expert Posts: 264 ✭✭✭
    Re: APS having issues with line quality?

    Dave,
    Have you tried to reset your voltage scale in TED Footprints to + or - 5% of 120 volts? (ie 114 to 126 volts which in Indiana a utility must conform) Much more granularity but it is personal preference. I like to see those spikes and refer the POCO to them every so often. Needless to say they monitor my feed a little bit better.
    23.16kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: APS having issues with line quality?

    dan,
    it's supposed to be the same voltages you cite here too. one thing is is that it is with no loads present to draw the voltage down. i had my utility come out and measure mine years back and mine was over what they were legally supposed to deliver. they pulled the meter to measure it to eliminate any loads possibly being present.
  • DanS26
    DanS26 Solar Expert Posts: 264 ✭✭✭
    Re: APS having issues with line quality?
    niel wrote: »
    dan,
    it's supposed to be the same voltages you cite here too. one thing is is that it is with no loads present to draw the voltage down. i had my utility come out and measure mine years back and mine was over what they were legally supposed to deliver. they pulled the meter to measure it to eliminate any loads possibly being present.

    Actually I have a good relationship with my REMC utility. When I first installed my TED system about 3 years ago I noticed voltage spikes on my line. I printed out the TED data in spreadsheet form and also the voltage graphs and presented the data to the REMC engineers. That got their attention since not many residential customers are monitoring their power supplies. My problem stems from being at the end of the line and many farms with large motor and welding loads.

    They soon fixed the problem with "line conditioners" which I believe were just large capacitors. Anyway, the line is very smooth now. When my solar system is producing well I will see a voltage rise of 2 to 3 volts but I attribute that to my own internal wiring.
    23.16kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring
  • DanS26
    DanS26 Solar Expert Posts: 264 ✭✭✭
    Re: APS having issues with line quality?

    Deleted faulty logic.
    23.16kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: APS having issues with line quality?

    no problem dan as i was not saying either of us had a problem dealing with our utilities as i merely pointed out how they designated it to be measured. yes, they use caps and that was the problem that was present here as the guy came out a second time to verify the voltage at my place and he said they had to eliminate some caps to correct my voltage.