Recent content by velowatt

Great idea- I have always thought that FETs fail catastrophically and permanently. I will check out the throttle. Thanks.

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There is one big MOSFEt in the center. It is a NDP77060L, which has max 75A continuous and 225 pen amp capability. On either side are two big switching diodes (HFA25TB60) rated at 25A each. These 3 components were folded down and attached with nylon bolts to a metal heatsink (Insulated from...

I have technical question for the ES brain trust! Been using an older bike for a short hilly commute to work. Throttle has an indicator with an on-off switch for the controller, and a 3-LED light system to indicate battery level (high, med, low). The brake levels have reed switches that cut...

I use LiFePO4 (Headway cells with BMS), have a 36V pack. The charger came from Mr. Ping, and crapped out after about a year of use (won't power up now at all). I recently knocked the charger off a shelf (2 foot drop to floor when I tripped over cord), so that may have destroyed it. I never...

Nice package! will you use BMS or single cell charger to balance the cells?

I would disconnect the BMS if the battery sits for long. Why discharge to 50%? I use my batteries during winter, so they get charged frequently. I have had good luck with free- standing BMS from Micjael at ev.assemble (using in 12s HEadway pack)

Forgive a stupid question- how does the charger discharge the cells. Mine charges them up.

I have a 15V inverter to power LED lights (rated at 12V)- got it from a surplus place for 4 bucks. It doesn't get hot and I can charge my cell phone too. Its a little brick about 2inches square.

Forgive me for replying to my own post- Michael Cheung of EV Assemble emailed this diagram to connect my BMS. Looks correct, but different than others I seen on the Forums. Update: Connected as above, pack seems to charge up. Interesting that the latter cells (7-12) in the string hit...

I have a Headway BMS (16s, 10Ah). Charger cuts off (light turns green) at 58.4V (3.65V/cell). Does balancing occur during charging, at the end of charging, after charging, or "all the time? I have cell logs on the pack (2 x 8s) which show that during charging a couple of cells are slower to...

I am repairing a 36V LiFePO4 (12 Headway 10 Ah cells in series) which was damaged by a failed BMS (took 6 of the cells down to zero volts without cutoff, the others remained above 2.8V and appear undamaged). I have replaced damaged cells, and bought a BMS board from evassemble. I want be be...

Those gizmos look nice, but expensive. I have an old cooling fan mounted over the controller heat sink. Runs off a little DC converter, uses abot 200 mA and keeps things cooool. Cost: zero.

These look like nice inexpensive supplies- Do you charge through a balancer that 'throttles' the charge down as the pack voltage comes up? I think things to concider are: (1) avoiding overcharging cells (explosions and fire), ({2) preventing over discharge during discharging (pack life and...

After i fried a Signalab BMS and toasted 5 of 7 Headway cells in my 36V pack, I have just gotten 2 cell log 8s. I had meant to charge the pack with a single cell charger and see how the pack works without any BMS once I replaced the damaged cells. I am in the process of installing the Cell...