Difference between revisions of "BMS"

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(Added commandline info for BMS master startup)
(Added info on 4 wire RS485 hardware)
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==Hardware==
 
==Hardware==
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The following pinout for the rs485 network does not appear to work. We believe the master is getting through to the slaves, in that they are responding, however there doesn't seem to be valid data returning to the terminal. Either that or the terminal is not receiving it correctly.
 
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'''''Initial Problem:'''''
  +
 
The pinout below for the rs485 network does not appear to work. We believe the master is getting through to the slaves, in that they are responding, however there doesn't seem to be valid data returning to the terminal. Either that or the terminal is not receiving it correctly.
   
 
This data was derived from first principles on two separate occasions, ending in the same design. Either there is a subtle double negative, incorrect data supplied, or the port is not set up as necessary. A further test with oscilloscope is required.
 
This data was derived from first principles on two separate occasions, ending in the same design. Either there is a subtle double negative, incorrect data supplied, or the port is not set up as necessary. A further test with oscilloscope is required.
  +
  +
'''''Problem Fixed:'''''
  +
  +
The reason this didn't work initially (as described above) was because we were using an RS485 JrMX box (which only supports two wire RS485 on pins 1 and 2). We actually need to be using an RS422 JrMX box which supports full four wire RS485 (on pins 1, 2, 3 and 4).
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FYI: The JrMX RS422 capable box (4 wire) is identified by the part numebr 3300MX GC'''22''' (the 2 wire version is 3300MX GC'''85''').
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===RS485 pinout===
 
===RS485 pinout===
   

Revision as of 08:14, 15 June 2015

We are using the Tumanako EVD5 BMS


Saker specific BMS info:

Software

Use the following commands to get the Saker's BMS master up and running:

Login: bms/bms

$ cd ~/bms-master
$ sudo modeprobe vcan && sudo ip link add type vcan && sudo ifconfig vcan0 up
$ build/main/monitor 2>/dev/null

or if you are using the alias short cuts:

$ cd_bms
$ setup_can
$ run_bms

Hardware

Initial Problem:

The pinout below for the rs485 network does not appear to work. We believe the master is getting through to the slaves, in that they are responding, however there doesn't seem to be valid data returning to the terminal. Either that or the terminal is not receiving it correctly.

This data was derived from first principles on two separate occasions, ending in the same design. Either there is a subtle double negative, incorrect data supplied, or the port is not set up as necessary. A further test with oscilloscope is required.

Problem Fixed:

The reason this didn't work initially (as described above) was because we were using an RS485 JrMX box (which only supports two wire RS485 on pins 1 and 2). We actually need to be using an RS422 JrMX box which supports full four wire RS485 (on pins 1, 2, 3 and 4).

FYI: The JrMX RS422 capable box (4 wire) is identified by the part numebr 3300MX GC22 (the 2 wire version is 3300MX GC85).


RS485 pinout

Master Slaves
Signal JRMX EVD5
TX-1 1 2
TX+1 2 3
RX-1 4 5
RX+1 3 4
GND 5 1
5V - 6

JrMXrs485.png

EVD5Rs485Sch.png

RS485 bias termination

This page has a good rs485 2/4wire and termination description

biasTermination.gif