New inverter or new CC

snuffy
snuffy Solar Expert Posts: 72 ✭✭✭✭
Here's what I have now. 5 evergreen 210's into an FM80 into a 1032 AH AGM 8D battery bank and a Xantrex Prosine 2 inverter/charger. I have 4, 215 watt evergreen panels waiting to be installed somewhere. The problem is that the FM80 won't handle that much wattage (1040+860) because of the 12 volt setup for the prosine. So my options are another FM80 for the 4, 215's and stay with a 12 volt system, or go with a bigger inverter/charger @24 volts or more. This will allow me to use just the one FM80 for all the panels as the FM 80 will handle all the panels at 24 volts or more. The bigger inv/chg will cost a lot more than the FM80 and I'd have the prosine 2 sitting on the bench all lonely feeling worthless. 2 FM 80's would give me redundancy if one pukes on me. Thoughts? Suggestions?

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New inverter or new CC

    Question: how much power do you use?
    In my opinion a 1000+ Amp hour 12 Volt bank is hideously large. It really would want more charge current than one FM80 can supply. If that's actually the kind of power you need/use (6 kW hours) you should up the system Voltage for that reason alone.

    You probably get about 50-60 Amps out of your existing array, which is pretty minimal for that much battery bank. Increasing the panels sounds like a good idea. If the new ones have the same Vmp as the old one you could parallel the strings except that you have five of one and four of the other. That little problem means either dropping one of the old panels, buying an additional 215 Watt unit, or getting a 2nd charge controller anyway.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: New inverter or new CC

    you could do it either way, but in general it depends on if you know that there won't be any changes after this one. i say that because a new cc would be cheaper than a new inverter/charger and with no plans of future expansions the cc would be the cheapest. any expanding in the future and then i'll say go for the inverter/charger and bigger battery bank voltages.
  • snuffy
    snuffy Solar Expert Posts: 72 ✭✭✭✭
    Re: New inverter or new CC

    Right now I'm running 2 refrigerators and a freezer off them. The FM 80 takes them to float each day if it's sunny. Varies from 4-5.5 KWH on the FM80.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New inverter or new CC
    snuffy wrote: »
    Right now I'm running 2 refrigerators and a freezer off them. The FM 80 takes them to float each day if it's sunny. Varies from 4-5.5 KWH on the FM80.

    I'm not surprised; you could actually supply that refrigeration with about 600 Amp hours, depending on how good the coolers are. The question is; are the batteries getting enough current to keep them from sulphating? Even AGM's sulphate; you just can't do anything about it with them. Your first clue may be when things shut down in the wee morning hours.

    How's that TLG working for you? They seem to be developing a reputation as one of the better small turbines. Mind you, it wouldn't take much to outclass most of 'em! :p
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: New inverter or new CC

    ok that's right now. if you expand that in the future as many do then it could necessitate another pv expansion down the road depending on how big the loads become. as it is right now with the need to expand the pvs to properly charge the battery bank i say the extra cc over the inverter/charger and i'm basing this on you right now. like i said a large change in loads could up everything and create the need for the inverter/charger change and that upward change could make the extra cc into a waste as the higher power is then handled by one cc at the higher battery voltages.

    bottom line-if you expand or think you could expand in the future beyond your present expansion then go with a new inverter/charger and keep it at the one cc. only you know what might be with you down the line and like i said, you can do this either way. it depends more on your possible future needs and your preferences along with considering costs if that's a factor.
  • snuffy
    snuffy Solar Expert Posts: 72 ✭✭✭✭
    Re: New inverter or new CC
    I'm not surprised; you could actually supply that refrigeration with about 600 Amp hours, depending on how good the coolers are. The question is; are the batteries getting enough current to keep them from sulphating? Even AGM's sulphate; you just can't do anything about it with them. Your first clue may be when things shut down in the wee morning hours.

    How's that TLG working for you? They seem to be developing a reputation as one of the better small turbines. Mind you, it wouldn't take much to outclass most of 'em! :p

    I will be increasing the charge current with the new panels and the TLG which isn't up yet. I just got the solar array up the beginning of May and before that the batteries got very limited use during power outages. Being recharged by the Prosine. My understanding from reading the battery manual is that they last longer if shallowly discharged and recharged every day. Which is pretty much what I'm doing. Though I'm not pumping a lot of current into them they do get a full charge every day. By the way thanks for the input.
  • snuffy
    snuffy Solar Expert Posts: 72 ✭✭✭✭
    Re: New inverter or new CC
    niel wrote: »
    ok that's right now. if you expand that in the future as many do then it could necessitate another pv expansion down the road depending on how big the loads become. as it is right now with the need to expand the pvs to properly charge the battery bank i say the extra cc over the inverter/charger and i'm basing this on you right now. like i said a large change in loads could up everything and create the need for the inverter/charger change and that upward change could make the extra cc into a waste as the higher power is then handled by one cc at the higher battery voltages.

    bottom line-if you expand or think you could expand in the future beyond your present expansion then go with a new inverter/charger and keep it at the one cc. only you know what might be with you down the line and like i said, you can do this either way. it depends more on your possible future needs and your preferences along with considering costs if that's a factor.

    Yes the extra panels were purchased for the extra charge current. The large battery bank because this is south east Michigan where the sun often disappears for quite a while in the short day months. Hope the TLG will help offset this issue a bit. I can probably get a Honda generator and the FM80 for the price of the inv/chg just occurred to me.
  • snuffy
    snuffy Solar Expert Posts: 72 ✭✭✭✭
    Re: New inverter or new CC

    I think the best bet is to go with another FM80 so I'll have more charge current going into my AGM's. Which can handle it quite easily. If I add more solar panels (the most likely scenario) and a larger, higher V inverter the extra CC can still be used and I'll have the redundancy of 2 CC's. So I wouldn't lose my entire solar potential if one of them pukes. If I decide to go with a larger inverter later I can still use the prosine with the FLA's I removed and replaced with the AGM's.