SMA sunny boy 6000 inverter input voltage?

rollandelliott
rollandelliott Solar Expert Posts: 834 ✭✭
I have a SMA 6000 inverter with the following specifications:
PV Array Connection
Maximum MPP voltage 250 V … 480 V
Range of input operating voltage 250 V … 600 V
Maximum generator input power 7,500 W
Maximum DC power 6,400 W
PV start voltage 300 V
Maximum DC input current 25 A
Maximum input short-circuit current 36 A

It will be hooked up to 28 of these panels:

Model ES-E-215-FC3
Power (W) 215 Watts
Open Circuit Voltage (V) 35.60 Voc
Short Circuit Current (A) 8.12 Isc
Maximum Power Voltage (V) 29.00 Vmp
Maximum Power Current (A) 7.43 Imp

It looks like the MPP voltage input needs to be between 250V to 480V.
My question is is their an optimum voltage? I see PVstart voltage is 300V so I guess that means it has to be at least that to start inverting power.

I was thinking of doing two rows of 14 panels each which is 35Vocx 14 = 490Voc per row, is that not going to work because it is over 480Voc? I could not find any kind of chart/curve on SMA's web site.

thanks!

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: SMA sunny boy 6000 inverter input voltage?
    Maximum MPP voltage 250 V … 480 V
    Range of input operating voltage 250 V … 600 V
    ....
    I was thinking of doing two rows of 14 panels each which is 35Vocx 14 = 490Voc per row, is that not going to work because it is over 480Voc? I could not find any kind of chart/curve on SMA's web site.

    Assuming the SMA spec. is correct... The unit will work up to Voc=600 VDC.

    It is just, when Vmp>480 volts--The unit will no longer "control and optimize" the Pmp=Vmp*Imp equation... And, typically, Voperational will be less than Vmp on warm days.

    If you live in an area with cool (and subfreezing) weather--then you may have an issue with Voperational>Vmp-stc. And want to look at other options (different controller, 1 less panel, different panels with lower Vmp and/or different series/parallel configurations).

    One place to start is with the Manufacturer's string sizing tool:

    http://america.sma.de/newstringsizing.aspx

    And follow their recommendations (and confirm that the numbers "make sense").

    One of the problems with string calculators--is they don't always have your panels listed... For example, the only 215 watt panel is:

    ES-A-215-fa2

    Which apparently is different from yours:

    ES-E-215-FC3

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: SMA sunny boy 6000 inverter input voltage?

    thanks! I think I made a mistake in my calculations though I did
    14panels x 35Voc = 490
    and it should of been
    14panels x 29Vmp = 406

    so I should be fine.