psw module

class psw.Psw

Bases: object

This module can control the PSW.

It supports USB interface to use SCPI.

It will scan available instruments on your DSO, then require a Serial Number to specify and connect to it.

Usage:

import psw
inst = psw.Psw()
inst.connect('<Instrument Serial Number>')
print(inst.idn())
inst.close()

clear_prot(): Clears over-voltage, over-current and overtemperature (OVP, OCP, OTP) protection circuits. It also clears the shutdown protection circuit.

close(): Close the connection.

connect(SN: str, baudrate: int = 115200, timeout: int = 3)

Connect to the PSW.

Parameters:

SN (str) – Serial Number is necessary.
baudrate (int, optional) – baudrate. Defaults to 115200.
timeout (int, optional) – timeout. Defaults to 3.

Returns:

0 or -1

Return type:

int

current() → float

Queries the current level in amps.

Returns:: output current
Return type:: float

idn()

is_ocp_on(): Returns the OCP (over-current protection) status.

is_on(): Returns output status of the instrument.

is_prot_trip(): Returns the state of the protection circuits (OVP, OCP, OTP).

max_current: MAX Current for this instrument. You will get it after connection.

max_voltage: MAX Voltage for this instrument. You will get it after connection.

meas_current() → float

Takes a measurement and returns the average output current

Returns:: output current
Return type:: float

meas_power() → float

Takes a measurement and returns the average output power

Returns:: output power
Return type:: float

meas_voltage() → float

Takes a measurement and returns the average output voltage

Returns:: output voltage
Return type:: float

min_current: MIN Current for this instrument. You will get it after connection.

min_voltage: MIN Voltage for this instrument. You will get it after connection.

mode() → str

Returns the output mode.

Returns:: output mode
Return type:: str

ocp()

Queries the OCP (over-current protection) level in amps.

Returns:: current
Return type:: float

opc()

ovp()

Queries the overvoltage protection level.

Returns:: current
Return type:: float

query(cmd: str) → str

Send a query SCPI command to the instrument and return the result.

Parameters:: cmd (str) – SCPI command to be queried.
Returns:: Result of the SCPI command.
Return type:: str

readline() → str

Read a line from the instrument’s communication port and return it as a string.

Returns:: The string read from the instrument.
Return type:: str

scpi_delay: SCPI delay.

set_current(value)

Sets the current level in amps.

Parameters:: value – (float) output current level. (str): MAX or MIN

set_mode(mode: int)

Sets the PSW output mode.

Parameters:: mode (int) – 0:’CVHS’, 1:’CCHS’, 2:’CVLS’, 3:’CCLS’,

set_ocp(current: float): Sets the OCP (over-current protection) level in amps.

set_ocp_off(): Turns OCP (over-current protection) off.

set_ocp_on(): Turns OCP (over-current protection) on.

set_off(): Turns the output off.

set_on(): Turns the output on.

set_ovp(voltage: float): Sets the overvoltage protection level.

set_scpi_delay(delay: float)

Set the SCPI delay

Parameters:: delay (float) – delay time

set_voltage(value)

Sets the voltage level in volts.

Parameters:: value – (float) output voltage level. (str): MAX or MIN

voltage() → float

Queries the voltage level in volts.

Returns:: output voltage
Return type:: float

write(cmd: str)

Write an SCPI command to the instrument.

Parameters:: cmd (str) – SCPI command to be written.