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#
# This file is part of the PyMeasure package.
#
# Copyright (c) 2013-2024 PyMeasure Developers
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
from pymeasure.instruments import Instrument, SCPIMixin
from time import sleep, time
import logging
log = logging.getLogger(__name__)
log.addHandler(logging.NullHandler())
class AMI430(SCPIMixin, Instrument):
""" Represents the AMI 430 Power supply
and provides a high-level for interacting with the instrument.
.. code-block:: python
magnet = AMI430("TCPIP::web.address.com::7180::SOCKET")
magnet.coilconst = 1.182 # kGauss/A
magnet.voltage_limit = 2.2 # Sets the voltage limit in V
magnet.target_current = 10 # Sets the target current to 10 A
magnet.target_field = 1 # Sets target field to 1 kGauss
magnet.ramp_rate_current = 0.0357 # Sets the ramp rate in A/s
magnet.ramp_rate_field = 0.0422 # Sets the ramp rate in kGauss/s
magnet.ramp # Initiates the ramping
magnet.pause # Pauses the ramping
magnet.status # Returns the status of the magnet
magnet.ramp_to_current(5) # Ramps the current to 5 A
magnet.shutdown() # Ramps the current to zero and disables output
"""
def __init__(self, adapter, name="AMI superconducting magnet power supply.", **kwargs):
kwargs.setdefault('read_termination', '\n')
super().__init__(
adapter,
name,
**kwargs
)
# Read twice in order to remove welcome/connect message
self.read()
self.read()
maximumfield = 1.00
maximumcurrent = 50.63
coilconst = Instrument.control(
"COIL?", "CONF:COIL %g",
"""Control the coil constant in kGauss/A. (float)"""
)
voltage_limit = Instrument.control(
"VOLT:LIM?", "CONF:VOLT:LIM %g",
"""Control the voltage limit for charging/discharging the magnet. (float)"""
)
target_current = Instrument.control(
"CURR:TARG?", "CONF:CURR:TARG %g",
"""Control the target current in A for the magnet. (float)"""
)
target_field = Instrument.control(
"FIELD:TARG?", "CONF:FIELD:TARG %g",
"""Control the target field in kGauss for the magnet. (float)"""
)
ramp_rate_current = Instrument.control(
"RAMP:RATE:CURR:1?", "CONF:RAMP:RATE:CURR 1,%g",
"""Control the current ramping rate in A/s. (float)"""
)
ramp_rate_field = Instrument.control(
"RAMP:RATE:FIELD:1?", "CONF:RAMP:RATE:FIELD 1,%g,1.00",
"""Control the field ramping rate in kGauss/s. (float)"""
)
magnet_current = Instrument.measurement("CURR:MAG?",
"""Get the current in Amps of the magnet.
"""
)
supply_current = Instrument.measurement("CURR:SUPP?",
"""Get the current in Amps of the power supply.
"""
)
field = Instrument.measurement("FIELD:MAG?",
"""Get the field in kGauss of the magnet.
"""
)
state = Instrument.measurement("STATE?",
"""Get the field in kGauss of the magnet.
"""
)
def zero(self):
""" Initiates the ramping of the magnetic field to zero
current/field with ramping rate previously set. """
self.write("ZERO")
def pause(self):
""" Pauses the ramping of the magnetic field. """
self.write("PAUSE")
def ramp(self):
""" Initiates the ramping of the magnetic field to set
current/field with ramping rate previously set.
"""
self.write("RAMP")
def has_persistent_switch_enabled(self):
""" Returns a boolean if the persistent switch is enabled. """
return bool(self.ask("PSwitch?"))
def enable_persistent_switch(self):
""" Enables the persistent switch. """
self.write("PSwitch 1")
def disable_persistent_switch(self):
""" Disables the persistent switch. """
self.write("PSwitch 0")
@property
def magnet_status(self):
"""Get the magnet status."""
STATES = {
1: "RAMPING",
2: "HOLDING",
3: "PAUSED",
4: "Ramping in MANUAL UP",
5: "Ramping in MANUAL DOWN",
6: "ZEROING CURRENT in progress",
7: "QUENCH!!!",
8: "AT ZERO CURRENT",
9: "Heating Persistent Switch",
10: "Cooling Persistent Switch"
}
return STATES[self.state]
def ramp_to_current(self, current, rate):
""" Heats up the persistent switch and
ramps the current with set ramp rate.
"""
self.enable_persistent_switch()
self.target_current = current
self.ramp_rate_current = rate
self.wait_for_holding()
self.ramp()
def ramp_to_field(self, field, rate):
""" Heats up the persistent switch and
ramps the current with set ramp rate.
"""
self.enable_persistent_switch()
self.target_field = field
self.ramp_rate_field = rate
self.wait_for_holding()
self.ramp()
def wait_for_holding(self, should_stop=lambda: False,
timeout=800, interval=0.1):
"""
"""
t = time()
while self.state != 2 and self.state != 3 and self.state != 8:
sleep(interval)
if should_stop():
return
if (time() - t) > timeout:
raise Exception("Timed out waiting for AMI430 switch to warm up.")
def shutdown(self, ramp_rate=0.0357):
""" Turns on the persistent switch,
ramps down the current to zero, and turns off the persistent switch.
"""
self.enable_persistent_switch()
self.wait_for_holding()
self.ramp_rate_current = ramp_rate
self.zero()
self.wait_for_holding()
self.disable_persistent_switch()
super().shutdown()
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