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1,498 Posts
Discussion Starter · #1 ·
This is the start of a project to create troubleshooting schematics for the 240vdc, 5amp version of these chargers, and this article covers a basic overview of the electronics inside the box. Pictures and sketches will be added as available.

The main analog power board is screwed to the heatsink. The big power semiconductors are clamped to a central standing set of plates thru the middle of the board/heatsink. The control board is mounted vertically on the edge of the analog board. Left side is AC input power, 160Vdc, and low voltage supply sections, on the right side is the H-bridge inverter, power transformer and 240Vdc supply, relay, fuse, output terminal strip.


1,498 Posts
Discussion Starter · #2 ·
Here's how to interpret the non-CAN serial port data stream that we were seeing on a 3kW charger (master-slave):

Byte, value, comment
0, 0xFF, first init code
1, 0xFE, second init code
2, 0xC5, destination descriptor
3, 0x0A, number of data bytes, 0Ah = 10
4, Version, uint8 VER;// 14h ='20'
5, RELAY ON/OFF flag, '1=ON(charging)
6, CUR_LV, float (byte 1 of 4) Current in amps
7, CUR_LV, float (byte 2 of 4)
8, CUR_LV, float (byte 3 of 4)
9, CUR_LV, float (byte 4 of 4)
10, HD_VOL_SET, float (byte 1 of 4) Voltage
11, HD_VOL_SET, float (byte 2 of 4)
12, HD_VOL_SET, float (byte 3 of 4)
13, HD_VOL_SET, float (byte 4 of 4)
14, checksum

So before the relay came on:

FF FE C5 = header info
0A = 10 bytes to follow
14 = version
00 = relay open
[BC CC CC CD] = -0.025 amps
[00 00 00 00] means zero volts
AA is checksum

Just before end of charge with a full pack:
01 means relay closed, charging
[3E 8C D9 39]= 0.275 amps
[43 31 DE B8] = 177.87 volts
9C is checksum

So it is now possible to use the serial port data to monitor the current and voltage during charging. Don't have the parameters to change voltage just yet, but it is coming soon...

you can use this calculator to get the float value from the 4 bytes:
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