Got the JK 3S-8S 200A 1A today

[hardtop]

I had previously bought a JK but it was used, DOA, missing manual, missing parts and I got ripped off on it. The replacement JK from another vendor arrived today and its working great on first try. The package came with everything and while the device itself was outside the wrapper, it looks a hella lot better than what the battery store gave me. Its like the battery store pulled a dead BMS out of the trash, threw it in an old box and sold it to me for $140.

One thing I'd like to change is the app. I tried paring to the BMS in my phone prior to opening the app, but the pair fails. The Overkill app doesn't see any devices. Is the JK locked into its own app or can I use other apps?

 

[740GLE]

Gotta use JK Software, JBD won’t work.

They use odd BT protocol so it won’t show up as say a Bluetooth speaker, but the app will recognize it once you download the proper app.

 

[hardtop]

Gotta use JK Software, JBD won’t work.

They use odd BT protocol so it won’t show up as say a Bluetooth speaker, but the app will recognize it once you download the proper app.

The app itself is working and it tells me what I need to know. The JK BMS case is nice too since it has eye holes to mount the unit.

The BMS behavior is a bit different than the JDB in that this morning on first full charge-up, the charger didn't throttle down gracefully. The JBD (and the charger in my car) would charge my pack at max until xyz and then it slowly drops the current to 0A. The JBD would take maybe 10 minutes to do its throttling or whatever the algorithm is doing. The JK just cut power from 30A and it was done charging. That seemed abrupt. Is it expected for each of those BMSes to behave differently?

 

[upnorthandpersonal]

What is your cell over voltage set at? The BMS will only cut off if it needs to protect the cells, e.g. over/under voltage etc. Take the time to run through the configuration options.

 

[hardtop]

What is your cell over voltage set at? The BMS will only cut off if it needs to protect the cells, e.g. over/under voltage etc. Take the time to run through the configuration options.

Cell OVPR(V) is 3.550v. My cells are EVE LF304's and it looks like max would be 3.65v. I'll try setting OVPR to 3.65 and see how it runs tomorrow.

 

[hardtop]

I tried setting OVPR to 3.65 and it gives me a write error. I'm probably doing it wrong lol. Should OVPR be set to 3.65? These are the settings:

 

[ChrisG]

I tried setting OVPR to 3.65 and it gives me a write error. I'm probably doing it wrong lol. Should OVPR be set to 3.65? These are the settings:

Your OVP should be 3.65. The OVPR (Recovery)must be lower like 3.60.

 

[hardtop]

Your OVP should be 3.65. The OVPR (Recovery)must be lower like 3.60.

Thanks for the help. I drained the battery down until the BMS cut it off and its taking 60A charge now for the past 4 hours. The interesting situation with the charging throttle-down is the Yamaha generator 75' away will also throttle down automatically to conserve fuel when the charger throttles. That's the only way I knew the charge didn't finish correctly lol. I need to start looking at the logs.

 

[hardtop]

Your OVP should be 3.65. The OVPR (Recovery)must be lower like 3.60.

After fixing those values the charger throttled down more gracefully. Fwiw, the 304AH pack took 5.07 kWh and 5 hrs 07 minutes to charge with a 60A charger.

I was thinking the Cycle Count should increment though. I ran the battery down until the BMS shutdown the output/inverter and then charged it all the way back up. Should Cycle Count be 1 instead of 0?