Help - I made the mistake of buying my own equipment but hiring installers. Battery issues.
- Thread starter Dkcampion
- Start date
Okay so I have some options now.
REC states I need a master controller and 2 BMS...the store I visited gave me a shopping list and it comes out to about $1800.
The battery maker has a hybrid inverter and charge controller option. the goal here is to keep using the new 4 VRLA batteries I bought to get the system up and running but also take advantage of the 2 Lifepo batteries that aren't currently working.
Keeping the SMA Sunny Boy and Sunny Islands in place, here is what I'm considering....give me your opinions.
borrow 2 strings (about 2 kw each) from the Sunny Boys and put them separately into the Hybrid inverter to charge these 2 batteries and then dump that separately into the loads panel. (total cost out of pocket about $600).
run 2 strings through a charge controller (not 100% sure how to work that out)...guessing a bus bar. (about $300 out of pocket)
just upgrade the BMS on the batteries ($1800).
REC states I need a master controller and 2 BMS...the store I visited gave me a shopping list and it comes out to about $1800.
The battery maker has a hybrid inverter and charge controller option. the goal here is to keep using the new 4 VRLA batteries I bought to get the system up and running but also take advantage of the 2 Lifepo batteries that aren't currently working.
Keeping the SMA Sunny Boy and Sunny Islands in place, here is what I'm considering....give me your opinions.
borrow 2 strings (about 2 kw each) from the Sunny Boys and put them separately into the Hybrid inverter to charge these 2 batteries and then dump that separately into the loads panel. (total cost out of pocket about $600).
run 2 strings through a charge controller (not 100% sure how to work that out)...guessing a bus bar. (about $300 out of pocket)
just upgrade the BMS on the batteries ($1800).
Hedges
I See Electromagnetic Fields!
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- Mar 28, 2020
- Messages
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I use a small AGM (VRLA) battery with Sunny Island. Best if they are kept floated, just supply surge current. I have a large PV/Sunny Boy array.
It would be nice to have lithium as a battery that charges when there is surplus, feeds power back whenever AGM battery is being drawn down, because lithium doesn't mind sitting partially charged.
Don't know of any off-the-shelf solutions, but imagine having an AC charger for the lithium battery enabled by a signal "AGM battery full", avoiding having Sunny Boys curtail output. And a 48V DC to DC charger transferring power from lithium to AGM enabled by a signal "AGM battery < 80% SOC" (which would require a battery shunt).
Alternate way to have lithium supply Sunny Island with its AGM would be inverter with lithium feeding AC into Sunny Island as "generator". Sunny Island would call for generator at some AGM SoC, while using AGM for starting surges as usual.
SMA also has Sunny Boy Storage, a 400V lithium inverter. As a system to power house it is limited to 6kW and has little surge capability, unlike Sunny Island. This wouldn't be the solution for OP, who has 48V lithium, but I've wondered if it could augment storage for my Sunny Island system.
It would be nice to have lithium as a battery that charges when there is surplus, feeds power back whenever AGM battery is being drawn down, because lithium doesn't mind sitting partially charged.
Don't know of any off-the-shelf solutions, but imagine having an AC charger for the lithium battery enabled by a signal "AGM battery full", avoiding having Sunny Boys curtail output. And a 48V DC to DC charger transferring power from lithium to AGM enabled by a signal "AGM battery < 80% SOC" (which would require a battery shunt).
Alternate way to have lithium supply Sunny Island with its AGM would be inverter with lithium feeding AC into Sunny Island as "generator". Sunny Island would call for generator at some AGM SoC, while using AGM for starting surges as usual.
SMA also has Sunny Boy Storage, a 400V lithium inverter. As a system to power house it is limited to 6kW and has little surge capability, unlike Sunny Island. This wouldn't be the solution for OP, who has 48V lithium, but I've wondered if it could augment storage for my Sunny Island system.
I setup my system for the first time yesterday and ran into some similar problems. I am using 48V LiFePO4 batteries with an internal BMS, so I was unable to use the Lithium Ion battery setting. I tried using the "Other" setting and setting the battery parameters myself, but I could never get the inverter started for some reason (perpetually in F141 InvVtgLo error mode). I eventually just left it the battery on VRLA and configured what I could manually. If anyone has ever gotten the "Other" battery to work, I'd love to know how.
In the meantime the UI is pretty annoying. Has anyone got a way to connect to a PC for configuration and monitoring? I saw a YT video of some guy hacking into using VenusOS but no instructions have been published.
In the meantime the UI is pretty annoying. Has anyone got a way to connect to a PC for configuration and monitoring? I saw a YT video of some guy hacking into using VenusOS but no instructions have been published.
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