Announcement

Collapse
No announcement yet.

4.57Kw PV with a 4Kw inverter. Inverter to small?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 4.57Kw PV with a 4Kw inverter. Inverter to small?

    Hi,

    I bought a 4.57Kw PV system (14x SunPower 327W panels) for my house last year.

    I now noticed that the installer fitted a SE4000 Solaredge which is limited to 4Kw.

    I can see from my stats that the system goes up to 3.98Kw but never above. It just goes flat and stays at 3.98Kw (especially in July/August when the PV generate most energy).

    Did the installer fit the wrong inverter?

    regards,

    tp


  • #2
    It is common practice to put an array with higher label ratings than the inverter because these ratings are for ideal conditions that the array will rarely see. Typical is to go 10 to 15% above the inverter size. You may be losing a few dollars of production during a few hours of the year, but it doesn't justify hundreds of dollars to go to the next size larger inverter.
    On the other hand, it may be wise to oversize an inverter to improve its reliability or allow for adding panels at a later date.
    BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installed

    Comment


    • #3
      so I take it you are not in the US, where we have an SE3800 instead of the SE4000. In any case, inverters are often slightly undersized. The SE5000 is not that much more expensive BUT it could be that the electrical codes and situations could dictate that other upgrades would have had to be done to get fit the larger inverter in.
      OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

      Comment


      • #4
        If the power is being limited because the panel orientation prevents 4.57KW. Then you have no resolution.
        On the other hand, if the inverter is clamping, and you have a warranty.
        Have the installer replace the inverter.
        Dennis
        SE5000 18 each SW185

        Comment


        • #5
          As Solarix notes, depending on where you are and the array orientation, you may see the array output approach the nameplate rating of the array infrequently, if at all, and if you do it may be only for brief periods of intense sunshine or when it's very cold.

          Disabuse yourself of the idea that an array will always, and as a matter of course, produce it's STC, or nameplate rating. That's sort of, but not quite the same as assuming your car's engine will produce its rated HP, every time you turn the key.

          Comment

          Working...
          X