eaps2000 1.2.1

Elektro-Automatik Series PS 2000 Python Controller

• eaps2000 - PS 2000B Series PSU Python Control Unit
  • Installing the package
  • Getting Started
    • Setup Linux Host
    • Using the CLI Interface
  • Running Tests
  • Building the Project
  • Documentation from the Manufacturer
    • Object List
• Debugging the System

eaps2000 - PS 2000B Series PSU Python Control Unit

The eaps2000 is a Python module for Elektro-Automatik PS 2000B Series PSU control.

This software implements the following functionality:

• Reading out device information (serial number, model etc.)
• Setting over-voltage and over-current protection
• Setting voltage and current for an output
• Controlling the output stage on/off
• Acknowledging alarms

Installing the package

Install the project from PyPi or build it first.

pip install eaps2000

Getting Started

Setup Linux Host

Check permissions on /dev/ttyACM0

ls -l /dev/ttyACM0

Add user to dialout group:

sudo usermod -aG dialout $USER
# if your distro uses uucp instead:
# sudo usermod -aG uucp $USER

Verify your groups:

groups

Make sure dialout (or uucp) is listed.

Close all other programs using /dev/ttyACM0:

lsof /dev/ttyACM0

Reboot your machine.

Using the CLI Interface

# Showing help
eaps2000 --help

# Show device info and current state (use /dev/ttyACM0 for Linux-based systems)
eaps2000 -p COM123 --info

# Set output voltage to 3.3V, current to 1.3A, output off:
eaps2000 -p COM123 -V 3.5 -I 1.3 --off

# Set output voltage to 3.3V, current to 1.3A, output on:
# CAUTION: This command will apply power to the output!
eaps2000 -p COM123 -V 3.5 -I 1.3 --on

NOTE: On Linux, use a device path such as /dev/ttyACM0 instead of COM123.

Using Python interface:

from eaps2000 import eaps2k

port = 'COM123'  # use /dev/ttyACM0 for Linux-based systems
with eaps2k(port) as ps:
    # Prepare config:
    cfg = eaps2k.get_config_template()
    cfg['ACK'] = True  # acknowledge alarms if any
    cfg['OVP'] = 5.0   # over-voltage-protection value
    cfg['OCP'] = 0.5   # over-current-protection value
    cfg['Iset'] = 0.1  # current to be set
    cfg['Vset'] = 3.3  # voltage to be set

    # Turn off the output stage:
    ps.set_output_state(False)

    # Apply configuration:
    ps.configure(cfg)

    # Turn on the output stage:
    # ATTENTION: The power will be applied to your probe here!
    # ps.set_output_state(True)

    # Show information:
    ps.print_info()

Running Tests

Install development dependencies first:

pip install -e ".[dev]"

Run unit tests:

pytest

Run tests together with flake8 checks (same mode as CI):

pytest --flake8

Run hardware tests (requires a connected PSU):

EAPS2000_RUN_HW_TESTS=1 \
EAPS2000_TEST_PORT=/dev/ttyACM0 \
pytest -m hardware

Run interactive hardware tests:

EAPS2000_RUN_HW_TESTS=1 \
EAPS2000_TEST_PORT=/dev/ttyACM0 \
EAPS2000_HW_INTERACTIVE_CONFIRM=1 \
pytest -m hardware_interactive -s

Building the Project

The project is built with hatchling

pip install hatchling && flake8 . -v && hatchling build && pytest --flake8

Installing a freshly built project can be done by running:

pip install ./dist/eaps2000-*.whl --upgrade --force-reinstall

Documentation from the Manufacturer

The manufacturer EA ELEKTRO-AUTOMATIK GMBH & CO. KG provides an overview of all available PS 2000 B Series models in the shop Serie PS 2000 B 100 bis 332 W on its German web page.

The Programming_Guide_PS2000B_TFT gives an overview of the protocol implemented. It also describes voltage/current conversions necessary for the communication.

Object List

Additional document object_list_ps2000b_de_en.pdf mentioned in Programming_Guide_PS2000B_TFT (or here and here) gives an overview of control commands. Each object in the list is basically a get/set command to control the PSU.

The table below lists objects in one place:

Object	Description	Access	Data type	Data length in Bytes	Mask for type 'char'	Data	Example or further description
0	Device type	ro	string	16			PS2042-06B + EOL (EOL= End of Line 0x00)
1	Device serial no.	ro	string	16			1034440002 + EOL
2	Nominal voltage	ro	float	4			Unom = 42.0 (Floating point number IEEE754 Standard)
3	Nominal current	ro	float	4			Inom = 6.0 (Floating point number IEEE754 Standard)
4	Nominal power	ro	float	4			Pnom = 100.0 (Floating point number IEEE754 Standard)
6	Device article no.	ro	string	16			39200112 + EOL
8	Manufacturer	ro	string	16			Manufacturer's name + EOL
9	Software version	ro	string	16			V2.01 09.08.06 + EOL
19	Device class	ro	int	2			0x0010 = PS 2000 B Single, 0x0018 = PS 2000 B Triple
38	OVP threshold	rw	int	2			Overvoltage set value 0-110% of Unom * 256
39	OCP threshold	rw	int	2			Overcurrent set value 0-110% of Inom * 256
50	Set value U	rw	int	2			Set value of voltage 0-100% of Unom * 256
51	Set value I	rw	int	2			Set value of current 0-100% of Inom * 256
54	Power supply control	rw	char	2	0x01 0x01 0x0A 0x10 0x10 0xF0 0xF0	0x01 0x00 0x0A 0x10 0x00 0xF0 0xE0	Switch power output on Switch power output off Acknowledge alarms Switch to remote control Switch to manual control Tracking on Tracking off
71	Status + Actual values	ro	int	6		Byte 0: Bits 1+0: Byte 1: Bit 0: Bits 2+1: Bit 3: Bit 4: Bit 5: Bit 6: Bit 7: Word 1: Word 2:	Query device state 00=free access; 01=Remote 1=Output on Controller state: 00=CV, 10=CC 1=Tracking active** 1=OVP active 1=OCP active 1=OPP active 1=OTP active Actual voltage (% of Unom * 256) Actual current (% of Inom * 256)
72	Status + Momentary set values	ro	int	6		Byte 0: Bits 1+0: Byte 1: Bit 0: Bits 2+1: Bit 3: Bit 4: Bit 5: Bit 6: Bit 7: Word 1: Word 2:	Query device state 00=free access; 01=Remote 1=Output on Controller state: 00=CV; 10=CC 1=Tracking active** 1=OVP active 1=OCP active 1=OPP active 1=OTP active Set value of voltage (% of Unom * 256) Set value of current (% of Inom * 256)

** PS 2000 B Triple only

Debugging the System

I very handy CLI option to see messages transfered on the bus is -vvv.

The command will show all the bytes transfered to and from the device.

eaps2000 -p /dev/ttyACM0 --info -vvv