Lake Shore 421 Gaussmeter

class pymeasure.instruments.lakeshore.LakeShore421(adapter, name='Lake Shore 421 Gaussmeter', baud_rate=9600, **kwargs)

Bases: Instrument

Represents the Lake Shore 421 Gaussmeter and provides a high-level interface for interacting with the instrument.

gaussmeter = LakeShore421("COM1")
gaussmeter.unit = "T"               # Set units to Tesla
gaussmeter.auto_range = True        # Turn on auto-range
gaussmeter.fast_mode = True         # Turn on fast-mode

A delay of 50 ms is ensured between subsequent writes, as the instrument cannot correctly handle writes any faster.

property alarm_active: Any: Get whether the alarm is triggered.

property alarm_audible: Any: Control the audible alarm beeper.

property alarm_high: Control the upper setpoint for the alarm mode in the current units. This takes into account the field multiplier.

property alarm_high_multiplier: Any: Get the multiplier for the upper alarm setpoint field.

property alarm_high_raw: Any: Control the upper setpoint for the alarm mode in the current unit and multiplier.

property alarm_in_out: Any: Control whether an active alarm is caused when the field reading is inside (“Inside”) or outside (“Outside”) of the high and low setpoint values.

property alarm_low: Control the lower setpoint for the alarm mode in the current units. This takes into account the field multiplier.

property alarm_low_multiplier: Any: Get the multiplier for the lower alarm setpoint field.

property alarm_low_raw: Any: Control the lower setpoint for the alarm mode in the current units and multiplier.

property alarm_mode_enabled: Any: Control the alarm mode.

property alarm_sort_enabled: Any: Control the alarm Sort Pass/Fail function.

property auto_range: Any: Control the auto-range option of the meter. Valid values are True and False. Note that the auto-range is relatively slow and might not suffice for rapid measurements.

property display_filter_enabled: Any: Control the display filter to make it more readable when the probe is exposed to a noisy field. The filter function makes a linear average of 8 readings and settles in approximately 2 seconds.

property fast_mode: Any: Control the fast-mode option of the meter. Valid values are True and False. When enabled, the relative mode, Max Hold mode, alarms, and autorange are disabled.

property field: Get the field in the current units. This property takes into account the field multiplier. Get np.nan if field is out of range.

property field_mode: Any: Control whether the gaussmeter measures AC or DC magnetic fields. Valid values are “AC” and “DC”.

property field_multiplier: Any: Get the field multiplier for the returned magnetic field.

property field_range: Control (floating) the field range of the meter in the current unit (G or T). Valid values are 30e3, 3e3, 300, 30 (when in Gauss), or 0.003, 0.03, 0.3, and 3 (when in Tesla).

property field_range_raw: Any: Control (integer) the field range of the meter. Valid values are 0 (highest) to 3 (lowest).

property field_raw: Any: Get the field in the current units and multiplier

property front_panel_brightness: Any: Control (integer) the brightness of the from panel display. Valid values are 0 (dimmest) to 7 (brightest).

property front_panel_locked: Any: Control the lock state of all front panel entries except pressing the Alarm key to silence alarms.

property max_hold_enabled: Any: Control the Max Hold function to store the largest field since the last reset (with max_hold_reset).

property max_hold_field: Get the largest field since the last reset in the current units. This property takes into account the field multiplier. Returns np.nan if field is out of range.

property max_hold_field_raw: Any: Get the largest field since the last reset in the current units and multiplier.

property max_hold_multiplier: Any: Get the multiplier for the returned max hold field.

max_hold_reset(): Clears the stored Max Hold value.

property probe_type: Any: Get type of field-probe used with the gaussmeter. Possible values are High Sensitivity, High Stability, or Ultra-High Sensitivity.

property relative_field: Get the relative field in the current units. This property takes into account the field multiplier. Returns np.nan if field is out of range.

property relative_field_raw: Any: Get the relative field in the current units and the current multiplier.

property relative_mode_enabled: Any: Control the relative mode to see small variations with respect to a given setpoint.

property relative_multiplier: Any: Get the relative field multiplier for the returned magnetic field.

property relative_setpoint: Control the setpoint for the relative field mode in the current units. This takes into account the field multiplier.

property relative_setpoint_multiplier: Any: Get the multiplier for the setpoint field.

property relative_setpoint_raw: Any: Control the setpoint for the relative field mode in the current units and multiplier.

property serial_number: Any: Get the serial number of the probe.

shutdown(): Close the serial connection to the system.

property unit: Any: Control (string) the units used by the gaussmeter. Valid values are G (Gauss), T (Tesla).

write(command)

Write a string command to the instrument appending write_termination.

Parameters:

command – command string to be sent to the instrument
kwargs – Keyword arguments for the adapter.

zero_probe(wait=True)

Reset the probe value to 0. It is normally used with a zero gauss chamber, but may also be used with an open probe to cancel the Earth magnetic field. To cancel larger magnetic fields, the relative mode should be used.

Parameters:: wait (bool) – Wait for 20 seconds after issuing the command to allow the resetting to finish.