Needs manual setup
Renogy RIV4835CSH1S + Fortress Power eFlex MAX 5.4
- Voltage matches: the 51.2 V battery suits this 48 V inverter.
- The inverter maker doesn't list this battery for closed-loop communication. The battery maker says it can run without communication, so you enter its charge settings on the inverter by hand.
Checked automatically against spec sheets. Not yet confirmed in a real install. Last checked 2026-10-12. We don't track firmware versions.
Size the battery cable and fuse for this pair in the build tool, from your run length.
What you'll set up yourself
-
Enter the battery's charge settings on the inverter by hand, in the battery
settings described in the inverter's manual.
- Max charge current: no more than 100 A per battery, from the battery's spec sheet.
- Charge voltage, float voltage, and low-voltage cutoff: from the Fortress Power eFlex MAX 5.4 manual.
Published limits, side by side
| Spec | Renogy RIV4835CSH1S | Fortress Power eFlex MAX 5.4 |
|---|---|---|
| Voltage | 48 V accepts 40–60 V | 51.2 V |
| Current | Max battery current 85 A | Max charge 100 A Max output 100 A Peak output 130 A |
| Communication | Open loop (no comms) | Sol-Ark closed loopGrowatt SPF/SPE closed loopOpen loop (no comms) |
| Cable connection | Stud size 5/16" | Terminal M8 |
Values come from each maker's documents. "Not published" means the maker doesn't state it.
Confirm with the makers before you buy
- Whether one battery can take the inverter's full current. The inverter's max battery current is 85 A. This battery is rated for 100 A charging and 100 A output. Ask how many batteries to run in parallel.
- Which firmware versions support this pairing. We don't track firmware.
- That your cable lugs fit the inverter's battery studs (5/16") and the battery's terminals (M8).
- How to install both safely, from each maker's manual and your local code.
This result checks two things: the battery's voltage suits the inverter, and the inverter maker lists this battery for closed-loop communication (the battery tells the inverter how to charge it). It doesn't check current limits, charge settings, firmware, cable sizes, or safe installation. Confirm those with both makers before you buy.
Sources
This result comes from the documents below. We haven't yet found an outside source that confirms it, such as a forum report or a video of a real install.
Where to buy
Renogy RIV4835CSH1S
- No store links yet. The maker's site is below.
- Renogy (maker)
Fortress Power eFlex MAX 5.4
- No store links yet. The maker's site is below.
- Fortress Power (maker)
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