SOMANET Test Suite - Controller for EA PSUs

Linux

Recommended step

Move 99-ea-psu.rules to /etc/udev/rules.d/ and restart udev with sudo service udev restart. This rule will create devices, that look like ea-ps-20xx-xx-0 or ea-ps-23xx-xx-0 with an increasing counter for every connected device.

Before start

To use ttyACMx devices without sudo, add your user to the group dialout:

sudo adduser your_user dialout

Windows

When connecting the power supply, Windows will install automatically the correct drivers.

Installing module

pip3 install ea_psu_controller

Import module

import ea_psu_controller

Create object

To connect to a particular PSU, you can call

Linux: psu = PsuEA(comport='ttyACM0')

Windows: psu = PsuEA(comport='COM1') or as com port description: psu = PsuEA(comport='PS 2000 B')

If you added the device rule and you connected only one PSU, there is no need to provide a device name:

psu = PsuEA()

Also possible is:

psu = PsuEA(comport='ea-ps-20xx-xx-0')

| If there is more then one PSU connected to the host, the script will connect to the first device found. | It is also possible to take the S/N written on the back of the PSU and call (dev rule on Linux needed):

psu = PsuEA(sn='0123456789')

or to use the device designator (dev rule on Linux needed):

psu = PsuEA(desi='PS 2142-10B')

Dis/connect to power supply for controlling

psu.remote_on()

psu.remote_off()

For multi output devices most functions provide a additional output argument:

psu.remote_on(output_num=0) or psu.remote_on(output_num=1)

| It's only necessary to call remote_on(), when you want to control the PSU. | If you just want to read device information, you don't need to.

Power on and off output

psu.output_on()

psu.output_off()

or

psu.output_on(output_num=1)

psu.output_off(output_num=1)

Set parameters

Arguments can be int or float.

psu.set_voltage(24)

psu.set_current(0.5)

psu.set_ovp(30)

psu.set_ocp(8)

The script will always set the maximum possible values in dependency of the nominal power.

| For example: | Nominal power = 160 W | If you set now the voltage to 40 V, it's not possible to set a higher current than 4 A (=160W/40V). | If you want to set a higher current, you need to decrease first the voltage.

Get parameters

Return argument: float.

psu.get_voltage()

psu.get_current()

Maximum sampling rate is ~10 Hz.

Get status

Return argument: dictionary

psu.get_status()

Dict contains following keys:

• 'remote on'
• 'output on'
• 'controller state' (CV=0, CC=2)
• 'tracking active'
• 'OVP activ'
• 'OCP activ'
• 'OPP activ'
• 'OTP activ'

Get device description

Return argument: tuple (name, SN)

psu.get_device_description()

Close connection

To close the connection, call:

psu.close(remote=False, output=False)

Set both arguments to True to turn off the output and remote control