The gas switcher is represented by the ophyd Device instance gas. Before
using, you must set the list of gasses like so:
gas.gas_list = ['N', 'Ar']
There may be up to six gasses, but you only need to specify the number that you plan to use.
To change gasses interactively, use the set method. It expects the gas name,
not the numerical position.
gas.set("N")
When gas is included as a "detector" or scanned like a motor, four things
are recorded in the database: the current and requested numerical position and
the current and requested gas name.
For example, this "scans" the gas switcher, triggering the pe1 at Nitrogen
and then at Argon.
list_scan([pe1], gas, ["N", "Ar"])
The ophyd Devices representing the temp controllers are named eurotherm and
cs700.
They can be used like any motor in a scan. For example:
dscan([pe1], eurotherm, -10, 10)
They can also be used interatively:
mov(eurotherm, 50)
A special feature of the eurotherm, not shared by the cs700, is a
configurable tolerance attribute. The tolerance is set to 10 in the startup
file, but it can be changed interactively.
eurotherm.tolerance = 15
Given the instability of the Eurotherm, a tolerance of 10 or greater is recommended.
When an RGA is included as a detector in a bluesky plan, it will automatically be started at the beginning of the scan and stopped at the end.
RE(count([rga], num=5, delay=1), LiveTable([rga]))