a.
You can connect the charger with the standard FTDI programming cable to your PC and issue
commands via the terminal application such as TeraTerm.
b.
Alternatively, you can control the charger directly from another microcontroller with UART TTL
serial line – such as another Arduino (UNO, Due, etc). Soon, we will be posting some Arduino
Sketches showing how it’s done.
c.
In either way, you would connect the control cable to the header on top of the small blue arduino
board inside the charger (you will have to open the charger box). Set the baud rate to 9600
d.
You will also need to disconnect the LCD by depressing the black round button on the bottom
right from the LCD. You need to do this before powering up the charger – the firmware checks for
LCD presence and defaults into Serial control ONLY if it does not detect LCD
e.
The current set of commands is as follows (for important applications please verify against the
firmware posted at ):
i.
Commands are contextual, with response depending on which state the charger is in right
now. Every command is an ASCII string starting with symbols 'M,' and ending with ',E'.
ii.
If the charger is in 'waiting for command' mode (signified by 1Hz 'READY' message
transmitted by the charger), the main command is 'M,ccc,vvv,E', where ccc is the CC
current and vvv is the CV voltage.
iii.
In the charging state, the charger will send an ASCII string with major parameters every
second. Format: 'M,D0,C965,V334,T-68,O1,R0,E' - [D]uty 0%, output [C]urrent 96.5A,
output [V]oltage 334V, heatsink [T]emp -68C, [O]utput charge 0.1AH, [R]untime 0
minutes.
iv.
In 'charging' state, the charger will accept a 'STOP' command. If issued once, the charger
pauses. If issued twice, the charger stops. If, after the first STOP command, a START
command is issued, the charger resumes. This is the same behavior as charger's response
to manual button inputs in the manual mode. In fact, same functions are used... RED
button is emulated by 'M,001,000,E' command, GREEN - by 'M,000,001,E'.
v.
This set obviously is a 'Minimally Viable' set that allows for automatic control of the unit.
Feedback welcome.
Thank you again for purchasing an EMW SmartCharge-25000HV intelligent open-source charger! We hope you
will enjoy the freedom of open source and will contribute to the community by sharing your adjustments to the
charger firmware.
Please let us know if you have any questions / suggestions / comments by emailing to
Thank you,
Valery Miftakhov
Founder, Electric Motor Werks