offgrider
New Member
- Joined
- Jul 20, 2020
- Messages
- 65
Thanks to all over the past 2 years who have helped me realize the dream I had when I was a kid and first started reading about solar!
The Solark/panels/optimizers (12K, QCells 440wattX26, TigoX26) were the easy part, I just had my electrical contractor do it all as the house was built. The DIY batteries were the complicated part, but ended up being very rewarding and fun project for me. I got 32 of the 280ah lifepo4s from lightning-power and capacity tested them all on my 40amp etech. They all were right around 285ah. Then paralleled them altogether for a top balance on that 40amp charger and got them to 3.6v and let them sit for a few weeks before assembling them into a 16s2p bank on an Orion JR2. This is roughly 30KwHrs.
The BMS proved to be tricky; the kit that was shipped wouldn't work as-is; I had to source what the BMS manual referred to as a "current amplifier" since the contactor that came as part of the kit has a 4amp coil inrush start and the BMS's signal outputs can only do 175ma. I ended up using a solid state relay in between the BMS and the contactor for this, it ended up being stupid simple. Speaking of which, the contactor that came in the kit (Gigavac MX23B) is great, it has built in suppression (no external diodes required) as well as a built in economizer. I powered the BMS/contactor from a wall outlet that is on the Solark's critical loads panel. The BMS and contactor when on only draws 5 watts (measured from the AC side of the power adapter Im using for it) The trick to the BMS though, was to not use the regular charge/discharge enable relay outputs. This BMS also has an output called MPE which is watchdog controlled just like the charge/discharge enables are, but it can be configured as output type of "contactor" and then can be set to remain on unless critical DTCs are thrown or if any cell's voltage or temperature goes too low or too high. The BMS also measures the cells' internal resistance, pretty neat.
So all yesterday evening and last night until this AM, the home ran completely from batteries, and are now charging back up in the sun!
Thanks again for everyone bearing with me!
That being said, I wouldn't really recommend this to anyone - the Orion support people (here in the US itsEwert Evolve) are just the worst. I still have lots of questions on the JR2 regarding pack health vs pack capacity, internal resistance, CANBUS comms, etc that all are behaving odd, and they are just awful to deal with. just terrible.
The Solark/panels/optimizers (12K, QCells 440wattX26, TigoX26) were the easy part, I just had my electrical contractor do it all as the house was built. The DIY batteries were the complicated part, but ended up being very rewarding and fun project for me. I got 32 of the 280ah lifepo4s from lightning-power and capacity tested them all on my 40amp etech. They all were right around 285ah. Then paralleled them altogether for a top balance on that 40amp charger and got them to 3.6v and let them sit for a few weeks before assembling them into a 16s2p bank on an Orion JR2. This is roughly 30KwHrs.
The BMS proved to be tricky; the kit that was shipped wouldn't work as-is; I had to source what the BMS manual referred to as a "current amplifier" since the contactor that came as part of the kit has a 4amp coil inrush start and the BMS's signal outputs can only do 175ma. I ended up using a solid state relay in between the BMS and the contactor for this, it ended up being stupid simple. Speaking of which, the contactor that came in the kit (Gigavac MX23B) is great, it has built in suppression (no external diodes required) as well as a built in economizer. I powered the BMS/contactor from a wall outlet that is on the Solark's critical loads panel. The BMS and contactor when on only draws 5 watts (measured from the AC side of the power adapter Im using for it) The trick to the BMS though, was to not use the regular charge/discharge enable relay outputs. This BMS also has an output called MPE which is watchdog controlled just like the charge/discharge enables are, but it can be configured as output type of "contactor" and then can be set to remain on unless critical DTCs are thrown or if any cell's voltage or temperature goes too low or too high. The BMS also measures the cells' internal resistance, pretty neat.
So all yesterday evening and last night until this AM, the home ran completely from batteries, and are now charging back up in the sun!
Thanks again for everyone bearing with me!
That being said, I wouldn't really recommend this to anyone - the Orion support people (here in the US its
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