Stacking Inverters question

2Guido
2Guido Solar Expert Posts: 62 ✭✭
Looking for a 220volt source to run larger appliances/pumps etc.....Is it possible to series wire 2 3k inverters (puresine) to create the 220 or does the sinewave have to be in correct cycle for this to happen ???
Thanks as always...you guys ROCK !!!

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Stacking Inverters question

    It only works if the two inverters are design to be stacked with each other. For instance you can take two Outback VFX's of the same model and stack them for 240 VAC output, but you can not take just any two inverters and do the same. One acts as "master" and the other as "slave", synchronizing to the master inverter so that the waveform of the output is correct.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Stacking Inverters question

    The only way is to buy two Inverters that can be slaved together so they coordinate the phase. Xantrex Prosine 2.0 can, Xantrex SW2024 can, Outback can , Magnum has a 240V output Inverter. I am sure there others.

    What happens is if you try to do it on the cheap, you have to be careful to keep the legs balanced and that can be tricky to do with your 120 v stuff. Small Inverters just do not lend themselves to it.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,599 admin
    Re: Stacking Inverters question

    Yes, it is possible to connect a pair if inverters in parallel (add current), or series to add voltage (120/240 VAC split phase). However, the inverters need to be designed for these applications and use a sync circuit+cable to do this. Not many inverters have this ability--and the ones that do are usually not cheap.

    The other method is to use a transformer to take the 120 VAC and make 240 VAC. Of course, the 120 VAC inverter(s) need to be capable of supplying the energy needed to run the loads. The transformer will double the output voltage, but will 1/2 the 120 VAC to 240 VAC output current (power=V*I, double the voltage, 1/2 the current for the same amount of power).

    Outback makes an "auto transformer" for these types of applications.

    Outback Power FW-X240 Auto Transformer

    Outback Power PSX-240 Auto Transformer
    http://www.outbackpower.com/pdf/manuals/fw-x240.pdf
    http://www.outbackpower.com/pdf/manuals/PSX-240_Installation_Manual.pdf

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset