Fluke8845A#

class Fluke8845A(visa_resource: str | VisaConfig)[source]#

Bases: Agilent34401A

Fluke 8845A 6.5-digit DMM, driven through its Agilent 34401A-compatible 8845 command set.

The meter’s default remote command set (8845) is compatible with the Agilent 34401A, so every command comes from Agilent34401A and this class adds none. Two front-panel settings must be made before use; neither can be changed over the remote interface, and both are non-volatile:

Command set 8845 (INSTR SETUP → COMMANDS → 8845). The Fluke 45 emulation command set is not supported.
RS-232 mode COMPUTER (INSTR SETUP → PORT IF → RS232 → COMP/TERM ECHO → COMPUTER). TERMINAL mode echoes each command and prints a NNN> prompt, which the driver reads back as the reply; open then fails with an error such as Fluke 8845A reported error: *CLS.

Over RS-232, also match the meter’s line settings to the VisaConfig defaults: 9600 baud, 8 data bits, no parity, 1 stop bit, no flow control, and EOL CR LF.

Create the driver; the connection opens on open.

Parameters:

visa_resource (str | VisaConfig)

VISA resource string, e.g. "ASRL6::INSTR" for RS-232 on COM6, or a VisaConfig to customize the serial line or backend.

Example:

from instro.dmm import InstroDMM, MeasurementFunction
from instro.unstable.dmm.drivers import Fluke8845A

dmm = InstroDMM(name="fluke", driver=Fluke8845A("ASRL6::INSTR"))
dmm.open()
dmm.set_measurement_function(MeasurementFunction.DC_VOLTAGE)
volts = dmm.read().latest
dmm.close()

Methods

`close`	Close the underlying transport.
`measure_ac_current`	Trigger an AC-current measurement and return the value (amperes RMS, vendor-dependent).
`measure_ac_voltage`	Trigger an AC-voltage measurement and return the value (volts RMS, vendor-dependent).
`measure_dc_current`	Trigger a DC-current measurement and return the value (amperes).
`measure_dc_voltage`	Trigger a DC-voltage measurement and return the value (volts).
`measure_four_wire_resistance`	Trigger a 4-wire-resistance measurement and return the value (ohms).
`measure_resistance`	Trigger a 2-wire-resistance measurement and return the value (ohms).
`open`	Open transport, `*CLS`, then `SYST:REM` to disable the front panel and RS-232 echo.
`set_ac_current_nplc`	Set AC-current integration time to `nplc` power-line cycles.
`set_ac_current_range`	Cache the range for `MEAS:...?` calls.
`set_ac_voltage_nplc`	Set AC-voltage integration time to `nplc` power-line cycles.
`set_ac_voltage_range`	Cache the range for `MEAS:...?` calls.
`set_aperture_seconds`	Set integration time directly in seconds.
`set_dc_current_nplc`	Set DC-current integration time to `nplc` power-line cycles.
`set_dc_current_range`	Cache the range for `MEAS:...?` calls.
`set_dc_voltage_nplc`	Set DC-voltage integration time to `nplc` power-line cycles.
`set_dc_voltage_range`	Cache the range for `MEAS:...?` calls.
`set_digits`	Set the digits (4, 5, or 6) used as the resolution argument in `MEAS:...?` commands.
`set_four_wire_resistance_nplc`	Set 4-wire-resistance integration time to `nplc` power-line cycles.
`set_four_wire_resistance_range`	Cache the range for `MEAS:...?` calls.
`set_measurement_function`	Configure the function for subsequent reads via a dummy measurement.
`set_two_wire_resistance_nplc`	Set 2-wire-resistance integration time to `nplc` power-line cycles.
`set_two_wire_resistance_range`	Cache the range for `MEAS:...?` calls.

close() → None#: Close the underlying transport. Idempotent.

measure_ac_current() → float#: Trigger an AC-current measurement and return the value (amperes RMS, vendor-dependent).

measure_ac_voltage() → float#: Trigger an AC-voltage measurement and return the value (volts RMS, vendor-dependent).

measure_dc_current() → float#: Trigger a DC-current measurement and return the value (amperes).

measure_dc_voltage() → float#: Trigger a DC-voltage measurement and return the value (volts).

measure_four_wire_resistance() → float#

Trigger a 4-wire-resistance measurement and return the value (ohms).

Default raises NotImplementedError; override on drivers whose instrument has dedicated sense leads (e.g. Agilent 34401A).

measure_resistance() → float#: Trigger a 2-wire-resistance measurement and return the value (ohms).

open() → None#: Open transport, *CLS, then SYST:REM to disable the front panel and RS-232 echo.

set_ac_current_nplc(nplc: float) → None#: Set AC-current integration time to nplc power-line cycles.

set_ac_current_range(value: float | None) → None#: Cache the range for MEAS:...? calls. The 34401A’s cache is shared across functions, so every set_*_range delegates here.

set_ac_voltage_nplc(nplc: float) → None#: Set AC-voltage integration time to nplc power-line cycles.

set_ac_voltage_range(value: float | None) → None#: Cache the range for MEAS:...? calls. The 34401A’s cache is shared across functions, so every set_*_range delegates here.

set_aperture_seconds(seconds: float) → None#

Set integration time directly in seconds.

Default raises NotImplementedError. Mutually exclusive with set_aperture_nplc on a given driver — vendors typically expose one or the other.

set_dc_current_nplc(nplc: float) → None#: Set DC-current integration time to nplc power-line cycles.

set_dc_current_range(value: float | None) → None#: Cache the range for MEAS:...? calls. The 34401A’s cache is shared across functions, so every set_*_range delegates here.

set_dc_voltage_nplc(nplc: float) → None#: Set DC-voltage integration time to nplc power-line cycles.

set_dc_voltage_range(value: float | None) → None#: Cache the range for MEAS:...? calls. The 34401A’s cache is shared across functions, so every set_*_range delegates here.

set_digits(n: int) → None#: Set the digits (4, 5, or 6) used as the resolution argument in MEAS:...? commands.

set_four_wire_resistance_nplc(nplc: float) → None#: Set 4-wire-resistance integration time to nplc power-line cycles.

set_four_wire_resistance_range(value: float | None) → None#: Cache the range for MEAS:...? calls. The 34401A’s cache is shared across functions, so every set_*_range delegates here.

set_measurement_function( function: MeasurementFunction, ) → None#: Configure the function for subsequent reads via a dummy measurement.

set_two_wire_resistance_nplc(nplc: float) → None#: Set 2-wire-resistance integration time to nplc power-line cycles.

set_two_wire_resistance_range(value: float | None) → None#: Cache the range for MEAS:...? calls. The 34401A’s cache is shared across functions, so every set_*_range delegates here.