DPS5005 power supply, remote control using python serial port modbus

Just a short one.
I bought one of these things.
It can do 50 volt 5 Amp, I have not looked at the quality of the output (noise, overshoot all unknown to me)  but should be alright to control a lamp, a battery or a strip of LED's is my guess.

You can easily control the current and voltage output using a serial port. (a usb-serial-rs485 was provided)

I seems to talk modbus protocol.

To change the baud rate and modbus-slave-address, keep POWER button pressed during power on, this will enter you into the configuration menu.

register list here :

Register Map for this device.

Function	Description	Number of bytes	Decimal places	UNIT	Read/Write	Register address
U-SET	Voltage setting	2	2	V	R/W	0000H
I-SET	Current setting	2	3	A	R/W	0001H
UOUT	Output voltage display value	2	2	V	R	0002H
IOUT	Output current display value	2	2	A	R	0003H
POWER	Output power display value	2	1 or 2	W	R	0004H
UIN	Input voltage display value	2	2	V	R	0005H
LOCK	Key lock	2	0	-	R/W	0006H
PROTECT	Protection status	2	0	-	R	0007H
CV/CC	Constant Voltage / Constant Current status	2	0	-	R	0008H
ONOFF	Switch output state	2	0	-	R/W	0009H
B_LED	Backlight brightness level	2	0	-	R/W	000AH
MODEL	Product model	2	0	-	R	000BH
VERSON	Firmware Version	2	0	-	R	000CH
EXTRACT_M	Shortcut to bring up the required data set	2	0	-	R/W	0023H
U-SET	Voltage settings	2	2	V	R/W	0050H
I-SET	Current setting	2	3	A	R/W	0051H
S-OVP	Over-voltage protection value	2	2	V	R/W	0052H
S-OCP	Over-current protection value	2	3	A	R/W	0053H
S-OPP	Over power protection	2	1	W	R/W	0054H
B-LED	Backlight brightness levels	2	0	-	R/W	0055H
M-PRE	Memory Preset Number	2	0	-	R/W	0056H
S-INI	Power output switch	2	2	-	R/W	0057H

Here is the test code I wrote, works for me, if it burns down your house, sorry but not my problem. I just post my example code, I make no claims about it.

#!/usr/bin/env python

import random

import minimalmodbus

minimalmodbus.BAUDRATE = 19200
minimalmodbus.TIMEOUT = 0.5  # must be low latency somehow??
minimalmodbus.CLOSE_PORT_AFTER_EACH_CALL = False


def decode_response(b):
    if len(b) != 20:
        print len(b)
        return

    rv = {'U-Set': b[0] / 100.0,
          'I-Set': b[1] / 1000.0,
          'U-Out': b[2] / 100.0,
          'I-Out': b[3] / 1000.0,
          'P-Out': b[4] / 100.0,
          'U-In': b[5] / 100.0,
          'Locked': {0: 'OFF', 1: 'ON'}.get(b[6]),
          'Protected': {0: 'ON', 1: 'OFF'}.get(b[7]),
          'CV/CC': {0: 'CV', 1: 'CC'}.get(b[8]),
          'ON_OFF': {0: 'OFF', 1: 'ON'}.get(b[9]),
          'Backlight': b[10],
          'Model': str(b[11]),
          'Firmware': str(b[12] / 10.0),
          }
    return rv


if __name__ == "__main__":

    instrument = minimalmodbus.Instrument(port='/dev/ttyUSB0', slaveaddress=1)  # port name, slave address (in decimal)
    # instrument.serial.baudrate = 9600
    instrument.debug = False  # True

    for i in range(1000):
        try:

            temp = instrument.read_registers(registeraddress=0x0,
                                             numberOfRegisters=20)

            print decode_response(temp)

            v = random.random() * 25.0  # between 0 and 25 volt output setting
            i = random.random() * 5.0  # between 0 and 5 amp output setting

            print "set to {v:2} V {i:2} A".format(v=v, i=i)
            instrument.write_register(registeraddress=0, value=v, numberOfDecimals=2) # set V
            instrument.write_register(registeraddress=1, value=i, numberOfDecimals=3) # set I

            # set Limit Current and Voltage protection values
            instrument.write_register(registeraddress=0x52, value=v, numberOfDecimals=2)  # set V
            instrument.write_register(registeraddress=0x53, value=i, numberOfDecimals=3)  # set I

        except (IOError, ValueError) as e:
            print e