PSU Device - MP711001 Driver

4-channel programmable power supply control library using SCPI protocol over Ethernet.

Device Info

• Model: Multicomp-Pro MP711001
• Type: 4-Channel Programmable DC Power Supply
• Interface: Ethernet (TCP Socket)
• Default Port: 5025
• Protocol: SCPI (Standard Commands for Programmable Instruments)

Installation

The MP711001 driver is part of the psu_device package:

from psu_device import MP711001

Quick Start

from psu_device import MP711001

# Connect to PSU
psu = MP711001("192.168.1.100")

# Set voltage on channel 1
psu.set_voltage(1, 5.0)

# Set current limit on channel 1
psu.set_current(1, 2.0)

# Enable output on channel 1
psu.output_on(1)

# Measure voltage and current
result = psu.measure(1)
print(f"Voltage: {result['voltage']}V, Current: {result['current']}A")

# Disable output
psu.output_off(1)

API Reference

Initialization

psu = MP711001(ip, port=5025, timeout=2)

Parameters:

• ip (str): Device IP address
• port (int): TCP port (default: 5025)
• timeout (float): Socket timeout in seconds (default: 2)

Channel Selection

select_channel(ch: int)

Select active channel for subsequent commands.

psu.select_channel(1)  # Switch to channel 1

Channels: 1, 2, 3, 4

Output Control

output_on(ch: int)

Enable output on specified channel.

psu.output_on(1)

output_off(ch: int)

Disable output on specified channel.

psu.output_off(1)

Parameter Configuration

set_voltage(ch: int, voltage: float)

Set output voltage on specified channel.

psu.set_voltage(1, 5.0)    # 5V
psu.set_voltage(2, 3.3)    # 3.3V
psu.set_voltage(3, 12.0)   # 12V

set_current(ch: int, current: float)

Set current limit on specified channel.

psu.set_current(1, 2.0)    # 2.0A limit
psu.set_current(2, 1.5)    # 1.5A limit

Measurement

measure(ch: int) -> dict

Read voltage and current from specified channel.

result = psu.measure(1)
# Returns: {"channel": 1, "voltage": "5.00", "current": "0.50"}

Returns:

• channel (int): Channel number
• voltage (str): Measured voltage
• current (str): Measured current

Low-Level IO

For advanced usage or custom SCPI commands:

write(cmd: str)

Send command to device (no response expected).

psu.write("OUTP ON")

query(cmd: str) -> str

Send command and retrieve response.

response = psu.query("MEAS:VOLT?")

REST API

Flask-based HTTP interface for remote access.

Starting the Server

cd psu_device
python -m flask --app flask_app run --port 5000

Server runs on http://localhost:5000

API Endpoints

POST /set

Set voltage and/or current on a channel.

Request:

{
  "channel": 1,
  "voltage": 5.0,
  "current": 2.0
}

Response:

{"ok": true}

POST /output

Enable or disable channel output.

Request:

{
  "channel": 1,
  "state": true
}

Response:

{"ok": true}

GET /measure

Read voltage and current from active channel.

Response:

{
  "channel": 1,
  "voltage": "5.00",
  "current": "0.50"
}

Common Patterns

Initialize Multiple Channels

channels = [
    {"channel": 1, "voltage": 5.0, "current": 2.0},
    {"channel": 2, "voltage": 3.3, "current": 1.5},
    {"channel": 3, "voltage": 12.0, "current": 3.0},
]

for ch in channels:
    psu.set_voltage(ch["channel"], ch["voltage"])
    psu.set_current(ch["channel"], ch["current"])
    psu.output_on(ch["channel"])

Ramp Voltage

import time

for v in [0.0, 1.0, 2.0, 3.0, 5.0]:
    psu.set_voltage(1, v)
    time.sleep(0.5)

Measure Power Consumption

result = psu.measure(1)
voltage = float(result["voltage"])
current = float(result["current"])
power = voltage * current  # watts

print(f"Power: {power}W")

Test with DC Load

Verify PSU output and regulation under load:

from psu_device import MP711001
from dcload_device import MP710771
import time

psu = MP711001("192.168.1.100")
dcload = MP710771("192.168.1.80", port=3000)

# Configure PSU
psu.set_voltage(1, 5.0)
psu.set_current(1, 2.0)
psu.output_on(1)

# Configure load and draw current
dcload.set_mode_current(1)
dcload.set_current(1, 1.0)
dcload.load_on(1)

time.sleep(1)

# Compare readings
psu_v = float(psu.measure(1)["voltage"])
load_v = float(dcload.measure(1)["voltage"])
print(f"Voltage sag under load: {(psu_v - load_v)*1000:.1f}mV")

dcload.load_off(1)
psu.output_off(1)

Verify Output with Multimeter

from psu_device import MP711001
from multimeter_device import MP730027

psu = MP711001("192.168.1.100")
mm = MP730027("192.168.1.99", port=3000)

psu.set_voltage(1, 5.0)
psu.output_on(1)

import time
time.sleep(1)

psu_reading = psu.measure(1)
mm_reading = mm.measure_dc_voltage()

print(f"PSU reports: {psu_reading['voltage']}V")
print(f"Multimeter measures: {mm_reading}V")
print(f"Difference: {abs(float(psu_reading['voltage']) - float(mm_reading))*1000:.1f}mV")

psu.output_off(1)

Error Handling

The driver automatically reconnects on socket errors. No explicit error handling required in most cases.

For custom error handling:

try:
    psu.set_voltage(1, 5.0)
    psu.output_on(1)
except Exception as e:
    print(f"Error: {e}")
    # Driver will attempt reconnect on next command

Performance Notes

• Timing: 0.1-0.15s delay between commands for stability
• Measurement: Single-shot, blocking. No polling loops.
• Reconnection: ~0.5s delay on error recovery
• Max Channels: 4 (indexed 1-4)

Specifications

Typical PSU specifications (refer to device manual for exact values):

• Voltage Range: 0-60V
• Current Range: 0-5A (per channel)
• Resolution: 0.01V, 0.001A
• Accuracy: ±1% typical

Troubleshooting

"Connection refused"

• Check device IP address: ping 192.168.1.100
• Verify device is powered on
• Confirm port 5025 is not blocked by firewall

"Socket timeout"

• Device may be overloaded; try increasing timeout parameter
• Check network latency

Measurements inconsistent

• Allow stabilization time after voltage/current changes
• See example in demo.py for recommended delays

Output won't enable

• Check current limit is set reasonably
• Verify load doesn't exceed PSU limits
• Try different channel

See Also

• Main documentation: ../README.md
• Example usage: ../demo.py
• Multimeter device: ../multimeter_device/README.md
• DC Load device: ../dcload_device/README.md