Unofficial Gamma ion pump ethernet control CLI utility and library

This is a mini Python 3 library and utility that exposes some of the functions of the Gamma Vacuum QPC ion pump controller via a CLI or via a library class via it's Ethernet port.

Note: This utility is in no way associated with Gamma Vacuum and is not an official product. It's just a simple tool that emerged out of my requirements to interact with their pump controllers. There is no guarantee that this utility will work under any circumstances, won't damage your controller or will work after firmware upgrades, etc.

Installation

This package can be installed by pip. Depending on the environment and operating system:

python -m pip install gammaionctl-tspspi

or simply

pip install gammaionctl-tspspi

In case one does not want to use pip one can also simply copy src/gammaionctl/gammaionctl.py and import from this file. There are no additional dependencies for the library.

Uninstalling

Uninstalling the package is also directly possible using pip if it has been installed that way:

python -m pip uninstall gammaionctl-tspspi

or

pip uninstall gammaionctl-tspspi

Library API

The library exposes a single GammaIonPump class inside the gammactl package.

Creating an instance / connecting

To connect to an ion pump controller one simply instantiates the GammaIonPump class passing the remote host address - one can either do this explicit and call close after one's done:

pump = GammaIonPump("10.0.0.11")
# ...
pump.close()

Or one can use the with construct which is highly encouraged:

with GammaIonPump("10.0.0.11") as pump:
    # Do whatever you want

There is a setVerbose method that one can use to dump debug information on stdout. This is primarily thought for debugging purposes during development though. To enable verbose mode one can simply execute

pump.setVerbose(True)

Error handling

All methods either:

• Return a value
• Return None in case there is no measurement value such as pressure for a disabled pump - in this case the connection stays active
• False in case of I/O or network errors as well as protocol violations. In this case the connection is dropped and no further commands are possible until one reconnects by reinstantiation of the connection object.

Identifying the controller

The identify method returns the identification string of the controller or False in case of failure.

Example:

id = pump.identify()
print(id) # Prints "DIGITEL QPC" for our controller

Getting estimated vacuum pressure

The pumps are able to estimate the current pressure inside the pump volume based on their pumping current. The pump index has to be 1-4 for the quad pump controller.

The method returns either:

• the pressure in millibar as float
• None in case there is no measurement value (for example because the pump is currently disabled)
• False in case of a protocol violation. Then the connection has been dropped.

# Querying pressure for pump 1
pressure = pump.getPressure(1)

Getting pump voltage

For every pump one can query the pump voltage of the ion pump using getVoltage. Again the pump index has to be 1-4 for the quad pump controller.

The method returns either:

• the voltage in Volts as float.
• None in case there is no measurement value. Note that for a disabled pump there is a standby current in the range of a few tens of volts that seems to be used to detect if there is an pump attached.
• False in case of a protocol violation. Then the connection has been dropped.

# Querying voltage for pump 1
volts = pump.getVoltage(1)

Getting pump current

For every pump one can query the pump current of the ion pump using getCurrent. Again the pump index has to be 1-4 for the quad pump controller.

The method returns either:

• the current in Millivolts as float.
• None in case there is no measurement value (for example for a disabled pump)
• False in case of a protocol violation. Then the connection has been dropped.

# Querying current for pump 1
amps = pump.getCurrent(1)

Querying the pump size

Using getPumpSize one can query the pump capacity of the pump in liters per second (L/S) for a pump index in the range from 1-4 for the quad pump controller.

The method returns either:

• the pump capacity in liters per second as int.
• None in case there is no configured size (in case no pump is connected for example)
• False in case of a protocol violation. Then the connection has been dropped.

# Querying pump capacity for pump 1
capacity = pump.getPumpSize(1)

Querying the current supply status

In addition (for human interfacing) one can query the supply status - the string shown on the controllers display - for every pump. This is done using getSupplyStatus again for a pump index in the range from 1-4 for the quad pump controller.

The method returns either:

• the pump status as string.
• False in case of a protocol violation. Then the connection has been dropped.

# Querying pump status for pump 1
status = pump.getSupplyStatus(1)

Starting and stopping a pump

To enable a pump that's currently disabled on can use the enable method, to stop a running pump the disable method. These methods of course also require the pump index. They either return True in case the operation succeeded (note this is idempotent so disabling a disabled pump is successful) or False in case of a protocol violation or connection error in which case the connection has been dropped.

# Enabling pump 1
pump.enable(1)
# Disabling pump 1
pump.disable(1)