NAME

Lab::Moose::Instrument::OI_Mercury::Magnet - Oxford Instruments Mercury magnet power supply

VERSION

version 3.902

SYNOPSIS

use Lab::Moose;

my $magnet = instrument(
    type => 'OI_Mercury::Magnet',
    connection_type => 'Socket',
    connection_options => {host => '192.168.3.15'},
    magnet => 'X',    # 'X', 'Y' or 'Z'. default is 'Z'
);

say "He level (%): ", $magnet->get_he_level();
say "N2 level (%): ", $magnet->get_n2_level();
say "temperature: ",  $magnet->get_temperature();

$magnet->oim_set_heater(value => 'ON');

say "Current field (T): ", $magnet->get_field();

# Sweep to 0.1 T with rate of 1 T/min
$magnet->sweep_to_field(target => 0.1, rate => 1);

See also an example of a He/N2 level plotter.

METHODS

The default names for the used board names are as follows. You can get the values for your instrument with the get_catalogue method and use the methods with the channel argument.

  • Temperature measurement: MB1.T1.

  • Level meter: DB5.L1

  • Magnet: Z (use DEV:GRPZ:PSU)

    The default can be changed to X or Y with the magnet attribute in the constructor as shown in SYNOPSIS.

get_catalogue

$mcat = $m->get_catalogue();
print "$mcat\n";

Returns the hardware configuration of the Mercury system. A typical response would be

DEV:GRPX:PSU:DEV:MB1.T1:TEMP:DEV:GRPY:PSU:DEV:GRPZ:PSU:DEV:PSU.M1:PSU:DEV:PSU.M2:PSU:DEV:GRPN:PSU:DEV:DB5.L1:LVL

Here, each group starting with "DEV:" describes one hardware component. In this case, we obtain for example:

DEV:GRPX:PSU     |
DEV:GRPY:PSU     |- a 3-axis magnet power supply unit
DEV:GRPZ:PSU     |
DEV:MB1.T1:TEMP  -- a temperature sensor
DEV:DB5.L1:LVL   -- a cryoliquid level sensor

In each of these blocks, the second component after "DEV:" is the UID of the device; it can be used in other commands such as get_level to address it.

get_temperature

$t = $m->get_temperature();
$t = $m->get_temperature(channel => 'MB1.T1'); # default channel is 'MB1.T1'

Read out the designated temperature channel. Result is in Kelvin.

get_he_level

$level = $m->get_he_level(channel => 'DB5.L1');

Read out the designated liquid helium level meter. Result is in percent as calibrated.

get_he_level_resistance

$res = $m->get_he_level_resistance(channel => 'DB5.L1');

Read out the designated liquid helium level meter. Result is the raw sensor resistance.

get_n2_level

$level = $m->get_n2_level(channel => 'DB5.L1');

Read out the designated liquid nitrogen level meter. Result is in percent as calibrated.

get_n2_level_frequency

$frq = $m->get_n2_level_frequency(channel => 'DB5.L1');

Read out the designated liquid nitrogen level meter. Result is the raw internal frequency value.

oim_get_current

$curr = $m->oim_get_current();

Reads out the momentary current of the PSU in Ampere.

TODO: what happens if we're in persistent mode?

oim_get_persistent_current

$field = $m->oim_get_persistent_current();

Read PSU current for persistent mode in Amps.

oim_get_field

$field = $m->oim_get_field();

Read PSU field in Tesla. Internally, this uses oim_get_current and calculates the field with the A-to-B factor.

Returns 0 when in persistent mode.

oim_get_persistent_field

$field = $m->oim_get_persistent_field();

Read PSU field for persistent mode in Tesla. Internally, this uses oim_get_persistent_current and calculates the field with the A-to-B factor.

oim_get_heater

$t = $m->oim_get_heater();

Returns the persistent mode switch heater status as ON or OFF.

oim_set_heater

$m->oim_set_heater(value => 'ON');
$m->oim_set_heater(value => 'OFF');

Switches the persistent mode switch heater. Nothing happens if the power supply thinks the magnet current and the lead current are different.

heater_on/heater_off

$m->heater_on();
$m->heater_off();

Enable/disable switch heater. Wait for 60s after changing the state of the heater.

in_persistent_mode

if ($m->in_persistent_mode()) {
   ...
}

Return 1 if in persistent mode; otherwise return false.

oim_force_heater

Switches the persistent mode switch heater. Parameter is "ON" or "OFF".

Dangerous. Works also if magnet and lead current are differing.

oim_get_current_sweeprate

$rate = $m->oim_get_current_sweeprate();

Gets the current target sweep rate (i.e., the sweep rate with which we want to go to the target; may be bigger than the actual rate if it is hardware limited), in Ampere per minute.

oim_set_current_sweeprate

$m->oim_set_current_sweeprate(value => 0.01);

Sets the desired target sweep rate, parameter is in Amperes per minute.

oim_get_field_sweeprate

$rate = $m->oim_get_field_sweeprate();

Get sweep rate (Tesla/min).

oim_set_field_sweeprate

$rate_setpoint = $m->oim_set_field_sweeprate(value => 0.001); # 1mT / min

Set sweep rate (Tesla/min).

oim_get_activity

Retrieves the current power supply activity. See oim_set_activity for values.

oim_set_activity

$m->oim_set_activity(value => 'HOLD');

Sets the current activity of the power supply. Values are:

HOLD - hold current
RTOS - ramp to set point
RTOZ - ramp to zero
CLMP - clamp output if current is zero

oim_set_current_setpoint

$setpoint = $m->oim_set_current_setpoint(value => 0.001);

Sets the current set point in Ampere.

oim_get_current_setpoint

$sp = $m->oim_get_current_setpoint();

Get the current set point in Ampere.

oim_set_field_setpoint

$m->oim_set_field_setpoint(value => 0.01); # 10 mT

Set the field setpoint in Tesla.

oim_get_field_setpoint

$sp = $m->oim_get_field_setpoint();

Get the field setpoint in Tesla.

oim_get_fieldconstant

Returns the current to field factor (A/T)

field_step

Return the minimum field stepwidth of the magnet

COPYRIGHT AND LICENSE

This software is copyright (c) 2024 by the Lab::Measurement team; in detail:

Copyright 2017       Simon Reinhardt
          2018       Andreas K. Huettel, Simon Reinhardt
          2019-2022  Simon Reinhardt

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.