Vicrton Smartsolar MPPT 75/15 - I want to disable the charge output to the battery when charging from a main supply charger. I understand you may be be to use the Rx pin on VE port to do this. Is this possible? and if so do I need a 5v signal or can I use 12v. Thanks in advance for any answers.
VE.Direct RX Port operation modes (register 0xED98)
Value
Description
0 : Remote on/off (*2)
1: Load output configuration (*2)
2 :Load output on/off remote control (inverted)
3 : Load output on/off remote control (normal) (*1)
Above are the available output modes. Whilst |I was waiting for my VE direct / USB dongle to arrive, I looked into the port voltages for normal signalling - these were 0 and -5V WRT gnd. So +12v on an input would probably be lethal (to the unit). So you would need to set the alternate mode 0, and then use an opto isolator with pull up resistor to drive the rx pin. then the resistor you use in series with the opto led will give you either 5 or 12v at your choice.
(refer to VE.Direct Protocol, BlueSolar and SmartSolar MPPT chargers)
Thanks I think I've solved the problem now. Pin 4 of the connector is +5v, so all I need to do is switch with relay contact between pin 4 and Rx. Surprised you measured -5v, the protocol is RS232 thought this was only +5v .
Description
0 : Remote on/off (*2)
1: Load output configuration (*2)
2 :Load output on/off remote control (inverted)
3 : Load output on/off remote control (normal) (*1)
I'm sure sure if I should create a new thread or just use this thread. I understand 3 or the 4 options for the RX pin of the MPPT, but can someone explain what the "Load output configuration" actually does?
