I got the cable its easy. All the epsolar (pwm or mppt) work with the same cable and are all rs232.

You can use any usb to rs232 plug you want. FTDI are around 14€ and prolific 2303 is around 3€ on ebay

The official epsolar cable is a prolific 2303. The ground is connected to the pin 8 of rj45 (read the protocol file in my first post, have the rj45 in front of you, pin visible the number 1 is on the left, the number 8 is far right)

Pin 5 (green on the official cable) is TXD on the rs232 board
Pin 6 (white) is RXD
Pin 8 (black) is GND

+5v is not connected

Thats it you can build your own cable.

Now I also have the same software that you show in the picture but it keep saying "cant connect to pv site"
I cut a rj45 cable and connect it to the lcd screen then sniffing the cable I m now able to monitor my epsolar with the code I gave you above.


There is still a lot of work but I do a bit more everyday.

Thanks for these specifications yohanndesbois!

Thank you very much

I start to work

Se e tutto corretto non funziona





la risposta e Can' t connect the PV Site!

la parte driver e cavo usb/rs232 senbra funzionare riconosce la porta e si apre ma poi non
dialoga con il regolatore

The official software is still early beta. It doesnt work for me neither. 'Can't connect to PV site' and sometime blue screen of death.

Are you sure your db9 serial port is rs232? Try to cross the TXD and RXD but it might not help.

By the way the baudrate is 9600.


I dont want to use the official software because its windows only and because its a raspberry pi who do the work (1watt).
I'm still working on my code.

What i'm trying to do now is: request/listen the serial port every second > compute an average for 1 minute > write it in a database.

Did you notice on the screen, the battery is full, then half then full again? Well it happen also in command line. Its because the controler send what it think to be overdischarge voltage and full battery voltage wich is different every time.
Thats why the screen is not precise. We must do better

blue screen of death for me to connect the cable after connecting the USB

And connecting usb cable only after the pc runs

By the way the baud rate is 9600. and ok

thanks anyway of help

If I find new information let you know

Sorry x translation with google

Thats fine you can speak italian, I'm french I understand a bit but I can't write it

Blue screen appear to be linked to the prolific driver.
The driver provided is from 2005, there is a newer on prolific website.

Maybe if you can try on a windows XP computer its gonna work (I only have windows 7 and linux computer).

I greatly improve my code today. It does ask 20 times, make an average, then write to database. Much quicker and lighter than before. Its even more precise than the screen.

I still need a good php developer to make a nice web page with graph and all.
I will write you an interface to make it easy but its not my priority as I need a web interface.

I tried connecting to an old pc with serial port

No blue screen

No connection to the controller

Se vi può servire io ho un 45Ah,non ancora usato,ho tradotto il pdf istruzioni in italiano,menziona il cavo incrociato etc etc

I have an MPPT EPSolar 20A with remote display, some Arduino programming skill and some php programming skill.

How can I participate to this project?

Ho risolto il mio problema grazie a bolle anche se non ha rispiosto

Regolatore epsolar viewstar vs4048 il problema era il monitoraggio da pc (non si trova il cavo) in parte quello scritto sopra era esatto.
quasi rassegnato leggendo un post di bolle sul interfaccia rs232 al pptea e venuto fuori un convertitore rs232 a ttl nello stesso momento ho ripensato alle specifiche del regolatore dove si parlava di connessione rs232/ttl.......1piu 1 eccola la .......
Serve interfacciare rs232 con un adattatore ttl con intregato max232 e tutto funziona i collegamenti descritti sopra sono giusti va solo interfacciato il convertitore lo schema di bolle funziona e pure la connessione al regolatore .

6 euro di componenti )

Cioè il display va a 3,3 volt e il PC a 12?!?

Per comunicare tramite suddetto Software con il regolatore serve un circuito son riuscito a realizzarlo anche se fa schifo ma funziona :



integrato pedinatura :



in pratica :






Risultato :





Il software di ep solar funziona ho testato tutto su view Star 40 A le connessioni dette sopra sono giuste ma serve il circuito

Ottimo saranno in molti che vi ringrazieranno .... complimenti a tutti

@Andrea AR ottima realizzazione