pehrlich
New Member
First time poster here - I hadn't seen much online about the DR E-series battery, so figured I'd share here.
The battery ($1,500): For context, I bought a new commercial mower last summer, and specifically bought the DR because it comes with three removable 2.5kWh batteries. (Unlike their sister company MeanGreen, which has the batteries permanently fixed). I thought it would be a fun and worthwhile experiment to get an inverter hookup for emergency backup power of my house - mostly freezers, a well, and internet, but more than my 1.5kW inverter (coupled to Chevy Bolt) could really handle.
Inverter ($300): The batteries are labeled for 120A @ 48V = 5.7kWh (see attached photo with label). After some searching online, I narrowed it down to a few options @ 4kW (8kW peak), as 5kW and 6kW seem uncommon. There are plenty of expensive choices which are set up for solar MPPT, or the ability to charge from solar or provide power from either battery or solar micro-inverters if it is the daytime (ac tie in of some sort, I forget the technical name). I decided to forego that extra complexity as it would require changes to my solar setup, and for the most part I just want to be able to handle the occasional multi-hour or day outage that we get in the the VT woods. A little manual setup is OK. I narrowed it down to the Renogy or a brand from China nobody's ever heard of, and went with the latter for $400 (now $300 on amazon). Interestingly they have the exact same user manual as other rando inverters, but I decided not to be put off by that and just went for it.
Wires: The inverter shipped with 4x 16mm^2 wires (two black, and two red). This comes out to somewhere between 2 and 4 AWG, which should suffice.
The Plug: Thanks to some help on Reddit, this was quickly narrowed down to an Anderson Coupling, 175 amp.
Circuit Breaker: I didn't want to worry about blowing a fuse during an emergency, so added a full-on car/RV circuit breaker (120A, 48V).
Assembly:
Overall, the hardest part was crimping the Anderson coupling, which I did with a ball bearing and a vice. A hydraulic crimper would have been easier, but I wasn't being picky.
First Run:
After plugging the battery in to the inverter and turning it on, I got an immediate low voltage beeping from the inverter, and the DV voltage quickly began to drop, even with zero load. I thought I was SOL here, as it kept doing this after several attempts. Then one time, it stopped erroring, and just worked - I think this may have been because I flipped the breaker a few times, maybe there was a bad connection in there.
Overall:
I'm please with the project, as have replaced a noisy/smelly/emissive generator for a ~$2k price point, rather than the $15k or whatever a full powerwall costs these days! In practicality, the price was even less, as I had the mower and don't use it in the winter when outages are the most common.
I should be able to run at least our 4-5 fridges/freezers, and I expect the well pump also, which runs at 1kW according to Sense (and would have a much higher initial draw). Not enough for the Heat Pump of course, but that's what wood-stoves are for
The battery ($1,500): For context, I bought a new commercial mower last summer, and specifically bought the DR because it comes with three removable 2.5kWh batteries. (Unlike their sister company MeanGreen, which has the batteries permanently fixed). I thought it would be a fun and worthwhile experiment to get an inverter hookup for emergency backup power of my house - mostly freezers, a well, and internet, but more than my 1.5kW inverter (coupled to Chevy Bolt) could really handle.
Inverter ($300): The batteries are labeled for 120A @ 48V = 5.7kWh (see attached photo with label). After some searching online, I narrowed it down to a few options @ 4kW (8kW peak), as 5kW and 6kW seem uncommon. There are plenty of expensive choices which are set up for solar MPPT, or the ability to charge from solar or provide power from either battery or solar micro-inverters if it is the daytime (ac tie in of some sort, I forget the technical name). I decided to forego that extra complexity as it would require changes to my solar setup, and for the most part I just want to be able to handle the occasional multi-hour or day outage that we get in the the VT woods. A little manual setup is OK. I narrowed it down to the Renogy or a brand from China nobody's ever heard of, and went with the latter for $400 (now $300 on amazon). Interestingly they have the exact same user manual as other rando inverters, but I decided not to be put off by that and just went for it.
Wires: The inverter shipped with 4x 16mm^2 wires (two black, and two red). This comes out to somewhere between 2 and 4 AWG, which should suffice.
The Plug: Thanks to some help on Reddit, this was quickly narrowed down to an Anderson Coupling, 175 amp.
Circuit Breaker: I didn't want to worry about blowing a fuse during an emergency, so added a full-on car/RV circuit breaker (120A, 48V).
Assembly:
Overall, the hardest part was crimping the Anderson coupling, which I did with a ball bearing and a vice. A hydraulic crimper would have been easier, but I wasn't being picky.
First Run:
After plugging the battery in to the inverter and turning it on, I got an immediate low voltage beeping from the inverter, and the DV voltage quickly began to drop, even with zero load. I thought I was SOL here, as it kept doing this after several attempts. Then one time, it stopped erroring, and just worked - I think this may have been because I flipped the breaker a few times, maybe there was a bad connection in there.
Overall:
I'm please with the project, as have replaced a noisy/smelly/emissive generator for a ~$2k price point, rather than the $15k or whatever a full powerwall costs these days! In practicality, the price was even less, as I had the mower and don't use it in the winter when outages are the most common.
I should be able to run at least our 4-5 fridges/freezers, and I expect the well pump also, which runs at 1kW according to Sense (and would have a much higher initial draw). Not enough for the Heat Pump of course, but that's what wood-stoves are for
