nope. AFAIK, the third pin used to be for the AGM thermistor and might be necessary for mower lockout during charging but I didn't care enough to look into it.
when viewing the plug bottom side down during insertion with mower: LEFT = - RIGHT = + TOP = N/C (it's probably easier just to buzz it out before connecting wires since the mower side is connected to the battery 24/7).
use up to 14A (?) per previous AGM chargery limited by the mower power...
and the best part of these "unhappy customer" threads is some of us will learn from other's mistakes and the state of the solar business.
I applaud your time and effort on this forum as customer support is at best difficult.
sorry, I'm not arguing your use case and BMS use.
I'm saying for a Ryobi RM480e lawn mower without a suspension, throwing in a $15 BMS with balancer adds more complexity and breakage possibilities (mechanically and electrically) than just using a simple charger once a year.
Difference of...
I was referring to 4S 12V batteries and I have a mistrust of cheap Chinese stuff without a track record in that environment. Mounting a BMS board in that Ryobi lawn mower (and your tiller less so because the mower is really bouncy) is placing too much faith in the structural integrity of the...
AFAIK, errors accumulate via coulomb counting via self discharge and accuracy of the measurement device. If you coulomb count only, it needs to be "reset" with some kind of "full charge" occasionally or you may run out of juice prematurely depending upon your usage / low Ah number to charge...
my owners manual says "The voltage needs to be tested at rest (with zero current) after 30 mins of disconnecting from the charger & loads."
I think the resting voltage gives you a gross estimate of SOC to tell if it's empty, full, or can be used some more. Really need to have a shunt battery...
AFAIK, the Ryobi AGM battery charger used it for charging (if you left out or disconnected the thermistor connected to the old batteries, it wouldn't charge) and on the mower side it locked out mower operation while charging.
If you don't want the AC coupled solutions mentioned previously with a separate backup load panel, get the Sol Ark 15K where your 200A main panel is the load. ~$8K.
https://www.sol-ark.com/wp-content/uploads/2022/04/15K_Specs_4_27_22-1.pdf
I think the payoff of extended life cycles combined with complication isn't worth it especially for a lawn mower application that sees relatively infrequent charge cycles.
For example, if you charge 100% SOC every time once a week and only get 1000 cycles, that's 20 years super conservatively...
FYI There's a facebook group for the RM480e.
I just converted mine with Ampere Time 12V 100Ah LiFePO4 batteries but was seriously considering going with 50Ah ones. The issue I have is whether the 50A max continuous discharge would be an issue or not with the Ryobi RM480e. I've mowed it twice...
Since you're using batteries in series for the mower, I'd want to re-balance them periodically, every 12 months (who knows?), not just at installation due to repeated high current discharge cycles. Too many unknowns and likely differences in chemistry with a "regular car charger".
Here's a...
True, OP could add a balancer or BMS instead.
I'm old school...I trust simple LiFePO4 charging technology (still made in China) over a $15 Chinese 4S 50/100A balancer/BMS. Simpler the better in a bouncing lawn mower.
NVM
ignore this stupid question...for those who want the perfect charging voltage from their charger, I finally found an awesome thread on LiFePO4, longevity, charge settings, etc. my takeaway as a Ryobi owner for me (and not in general):
- install an accurate coulomb counting battery monitor...
If you are talking about a Li-Ion 13S 54.6V charger running at 10A, very likely regardless of how they implement a charging algorithm because of the relatively low current it's hard to screw it up.
Personally, I'd just get a 58.4V LiFePO4 16S charger and get the last few % (?) charge and maybe...
58.4V is recommended for 16S LiFePO4. I was thinking LiFePO4 15S or Li-Ion 13S would be fine. This situation would only matter if you had a faulty battery or wanting a slightly lower SOC.