MiniBMS Fixed

Previously, my MiniBMS was in the state of constant alarm.  It happened one day, long ago when I was backing out of the driveway when the alarm started buzzing and just wouldn't stop. I drove it home and from there, it's been an off and on project throughout the winter.  For the meantime I would recharge the battery pack by bypassing the MiniBMS charger relay and manually control the current and do a top charge every now and then.

Since I was convinced it was the MiniBMS headboard that was at fault, I bought another one.  I installed it and felt like Einstein's definition of insanity - not the workout, the madness.  NO CHANGE.  Domitri, the guy that owns MiniBMS stated in an email he thought it was a "wiring problem."

Remember the fire I had sometime ago?  When I went poking around I found some crispy wires that sure needed to be replaced.  After that I completely rewired the MiniBMS headboard with all new wires.  Then I decided I should check all the cell boards. I was shocked to see 10.4 Volts coming from the cell loop.  I tested most of them and found a board that was stopping the flow completely.  I hit the emergency disconnects, disconnected the DC to DC and replaced the board - I have a few extras on hand.  Then when I tested the cell loop again I got 0.7 Volts flowing from all the boards.

I took the car for a quick drive and voila! The light for the charger came on when I turned off the car.  I then went to radio shack and connected a new buzzer to the headbaord and there was no sound. Yes!!! Thank you, Lord!  Then I disconnected one of the cell boards from the loop and the buzzer went off. (stand test to make sure the buzzer is working)

I'm not completely sure what was at fault but either way, it's back to working.  Now if the rain here would stop so I can drive it.

At one point I was looking at the possibility of buying another BMS.  There's a neat page on the Lithiumate site that compares all known BMSs.  http://liionbms.com/php/bms_options.php If one would combine the monitoring capability of the BlueWindow and the reliability of the MiniBMS with the capability to top charge/discharge as necessary and provide real time individual cell monitoring, I'd buy it.  The Lithiumate Lite comes close, but it isn't cheap - $1300 was what I priced my set up at. Then I'd have to find a computer to put in the car for real time displays. For now, I'll stick with what I have.