BAC-028X SOA Voltage ranges

[Sam.Vanratt]

Hi all
I'm in search for the Safe Operation Area of the BAC controller, esp. the 281 for 24V. Because of my other thread
https://goldenmotor.com/SMF/index.php?topic=6634.0
I'm willing to exchange my battery as well (from LiFePO4 to LTO, therefore the voltage of the complete pack changes from 25,6V (8S) to 28,8V (12S)), so the controller itself needs to accept the different range (24V lower point and 28,8V upper range to the LTO range of 25,6 to 32,6V upper range). Stupid controller have fixed "windows" specifically for a certain usual chemistry.
I've not found any information of the exact ranges so I ask here for some insight. The BAC controller seems so much identical to my internal MP3 one, so I prefer to get this one instead of switching to some others like the VESC.
Cheers
Sam

[Bikemad]

Hi Sam

As far as I am aware, the BAC-028*P external controllers are the same size, shape and pin configuration as the earlier MPII controllers but obviously enclosed within a protective plastic case.





The MPII controllers could be programmed for 24V, 36V or 48V, but would run on any of the above voltages regardless of the programmed setting.

The 24V setting was often used with 48V battery packs as it seemed to produce more torque, and I presume the external controllers will be the pretty much the same.

I suggest that you also purchase the PI-200E USB programming lead, just in case the current has been set very low for use with the MBG36F/R geared mini motors. 


The MPIII should be relatively easy to convert for use with an external controller as shown here:





I hope this information helps.

Alan
 

[Sam.Vanratt]

Hello Alan
 that's important to know (overvoltage) as I thought the BAC is an ext. Pie3 kontroller (so a bit more modern... FET, uC, size, ....). The MP3 controller has (to my knowledge) an overvoltage protection so the controller stops working outside this "window", mabye to prevent overcharge to the batteries (Lithium) by rekuperation source. With my 29V I'm pretty far of the curve, so not every controller will work, exp. the more intelligent ones stop working and the real intelligent ones (window configurable) are usually too expensive, bulky, ....
So the BAC seems the right controller to drive my Pie3 again. I'll put one or even two in stock, as time seems to get rid of the "great" MagicPie3 era. I'm already in contact to Gary for two+ BAC controllers as it seems no one else at stock in the (whole) EU.

Thanks again Alan; I might take photos so the refurbishment process is described once and for all

Sam