Search found 56 matches

by arber333
Tue, 16 Apr 2013, 19:51
Forum: Batteries, charging, management and monitoring
Topic: Low cost BMS
Replies: 443
Views: 73226

Low cost BMS

yes, you told me, i repent :). I am using 1W dcdc galvanicaly isolated module 10-20V in and 12v out. All comms are utp but the short lines directly from master that i use to connect switches to. When i have the comms up and running 39cells i then take the last wire (comm in) and disconnect from modu...
by arber333
Fri, 05 Apr 2013, 23:35
Forum: Batteries, charging, management and monitoring
Topic: Low cost BMS
Replies: 443
Views: 73226

Low cost BMS

Ok I solved my problem. Since some of you are working on your BMS i guess it is good to explain. I changed comm lines to soft UTP computer cable. The thing is thin! But it works very good. I now have comms stable through all RPM and up to 200A (havent tried it faster :)). However when i start to tak...
by arber333
Thu, 14 Mar 2013, 00:05
Forum: Batteries, charging, management and monitoring
Topic: Low cost BMS
Replies: 443
Views: 73226

Low cost BMS

@ bga: By close you mean R8 proximity to opto mounts? Actually i just copied that :). The skinny track has auxiliary function as a fuse in case something would happen on the Pic supply line. Washer is actualy the M8 normal one, i use it with thin springy lockwasher. It covers most of the plating, i ...
by arber333
Tue, 12 Mar 2013, 13:44
Forum: Batteries, charging, management and monitoring
Topic: Low cost BMS
Replies: 443
Views: 73226

Low cost BMS

I tested individual banks for balancing and the cells were balancing fine for 1/2 hour or so. No trouble here. However i must have connected the comms wrong after final assembly and in the process 3 modules got zapped. I mean pic12F was blown off in smoke. But heres the kicker: every burnt module wa...
by arber333
Tue, 12 Mar 2013, 04:29
Forum: Batteries, charging, management and monitoring
Topic: Low cost BMS
Replies: 443
Views: 73226

Low cost BMS

Attached is my cell PCB. I connected 3R3 between fat tracks on the + side. Underneath i kept copper plating to dissipate heat. So far with single and 4 pack modules there werent any problems. Cells were shunting happily at 1A. The trouble started with current master build. This is why i suspected op...
by arber333
Mon, 11 Mar 2013, 06:49
Forum: Batteries, charging, management and monitoring
Topic: Low cost BMS
Replies: 443
Views: 73226

Low cost BMS

Hi, I am currently experimenting with Nevilles BMS, the low balancing version. I have two issues now. I have 40 cells and 130VDC system. System works very well and shows all parameters untill i press the pedal and drive. At that time master shows over 300V and over 60 cells!!! I have three banks of ...