Dilemma new inverter or two charge controllers

Discussion about the FM100, FM80, and FM60 Charge Controllers

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My RE system: outback fm 60

Dilemma new inverter or two charge controllers

Post by rickdemers »

Hi Guys
Here is my dilemma I have a very nice royal pure sine 3000 watt inverter, with a 9000 peak ,that works very well with my jet pump as it needs over 6500 watts on start up and has energy saving mode ,where the unit is not inverting power when there is no demand ,it just send out a pulse every 3 or 4 seconds , so no power lost overnight and one more thing is I just picked up another same unit for $300 as spare with only I year use on weekend , but this inverter is a 12 volt only .so stuck with 12 volt battery bank , and currently using a FM 60 with 3 solar panels , And now I what to install another 8 panels at 220 watts each , I am leaning towards purchasing Two outback FM 80 as this would be cheaper to take the amount of panels , or do you suggest I go to a new inverter and I would still need a other charge controller ,
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My RE system: Flexpower Two: (2) FXR3048A, (2) FM80, MATE3s, FlexNetDC
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Suniva 330 watt panels (12 - 6 strings of 2 in series)
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Re: Dilemma new inverter or two charge controllers

Post by raysun »

It is a dilemma.

A nice thing about additional charge controllers is they are very long-lived, and can be used with any battery in the future. Not necessarily so with the inverters. An Outback FM80 is about US$500, and will support a PV array of 1000W at 12V.

A 3kW Outback inverter will cost around US$1800. A rugged, capable unit to be sure, and 48V is more efficient. The 48V battery configuration will permit 2880W PV panel array on a single FM60.

Additional panels in both cases will have the
same cost/watt.

If offgrid, having controller redundancy is a good thing.

If the inverter is doing the job, additional PV array/controller capacity will be helpful. By the time the battery needs replacing, the inverter may be a candidate for consideration as well.
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