GEM Instrument Details - ISISComputingGroup/ibex_developers_manual GitHub Wiki

This page collects information that will be useful for the implementation of the IBEX control system on GEM.

Background & Timeline

GEM is a diffractometer instrument at ISIS, on TS1. The GEM web page describes the background to the instrument.

Control System

GEM will migrate from the SECI control system to the IBEX control system in summer 2017. During the summer 2017 shutdown, new jaws will be installed on GEM.

GEM Equipment

The equipment listed below is used on GEM. Please add new information (e.g. new items of equipment, new notes, information about drivers, etc. to this table).

Manufacturer Model Type Connection Driver Notes
ISIS DAE 2 Detector Electronics Ethernet see DAE note
ISIS Mk2 Chopper Chopper RS-232 see #2130 see Chopper note
GALIL DMC2280 Motion Controller Ethernet EPICS
??? 5 x 4-blade jaws see Jaws note
??? 1 x 4-blade jaws "Beamscraper" Jaws see Jaws note
ISIS Collimator Oscillating Radial see Collimator note
ISIS ??? ISIS Vacuum System see Vacuum System note
Eurotherm Temperature Controller All models at ISIS RS-232 EPICS see Eurotherm note
Oxford Instruments Orange Cryostat Cryogenic System see Oxford Instruments note
Oxford Instruments Blue Cryostat Cryogenic System see Oxford Instruments note
Oxford Instruments Dilution Fridge (Kelvinox) Cryogenic System see Oxford Instruments note
Closed Cycle Refrigerator see CCR note
ISIS GEM-Furnace Furnace see ISIS Furnaces note
McLennan PM600 Motion Controller RS-232 EPICS see McLennan note
ISIS GEM Sample Changer Sample Changer RS-232 Same as POLARIS sample changer. See #2173
MKS PDR2000 Pressure Transducer RS-232 see #1406 and #1620
Pfeiffer TPG300 Vacuum Gauge RS-232 EPICS see #216 and #2063

From time-to-time, GEM has also used magnets, gas handling and high-pressure systems, but not frequently.

Note: DAE

Main Detector banks + fixed monitors.

Note: Choppers

3 choppers: 2 double-disk and one T0 chopper. Choppers are ISIS Mk2 choppers. Mk2 choppers have a serial interface (not Ethernet like Mk3).

Note: Oscillating Radial Collimator

The oscillating radial collimator is currently driven by a McLennan system, controlled via a custom controller at present. At some point this controller is going to be replaced by a Galil system, but this will not be done by September 2017.

There have been instances where the collimator stops responding (see: https://github.com/ISISComputingGroup/IBEX/issues/3167). These cases present as the device responding to status requests, but not acting on requests to reinitialise or start the oscillator. In this case, the device has to be power-cycled. To do this, it must first be switched off via the front panel, then the power cable must be removed. Leave the device for several seconds before reconnecting and switching back on. If successful, the number of cycles should reset to zero.

Note: Jaws

GEM has 5 four-blade jaws and one bespoke set of jaws (called the "beam-scraper"). For the "beam-scraper" jaws - see #2138 The 5 four-blade jaws were due to be replaced with Galil driven units during summer 2017. However, as of May 2017, the upgrade has been postponed: From Ivan da Silva: Finally, due to other instrument works’ priorities, the GEM works for replacing the jaws will not be carried out during the next summer shutdown, but during winter 2017/2018. Then, for 2017/02 cycle we will be still using the same jaws sets as for now. In principle, we will start using the new jaws on cycle 2017/04 (Feb-Apr 2018). Therefore, all jaws on GEM will continue to be controlled by LinMot controllers until, at least, cycle 2017/04. Confirmed by Nick Webb (04-07-2017): new GEM jaws, controlled by Galil, will be installed in November 2017.

Note: Vacuum System

GEM does not need to control the vacuum system, but it does need to be able to view and log vacuum gauge readings.

Note: Eurotherm

Used to control temperature Orange Cryostat, CCR and Furnace devices.

Note: Oxford Instruments
  1. Orange Cryostat: models to be determined. Orange cryostats are controlled via a temperature controller (e.g. Eurotherm), so nothing on the cryostat itself for IBEX to control.
  2. Blue Cryostat: models to be determined.
    1. Are these the Heliox and ITC devices?
    2. The Heliox device has a sorption insert (is that relevant to the control system?)
  3. Dilution fridge: models to be determined.
    1. Kelvinox dilution fridge

Note: Closed Cycle Refrigerators

CCRs. Not directly computer-controlled - controlled via Eurotherm.

Note: ISIS Furnaces

More information on IRIS Furnaces. GEM uses:

  1. GEM Furnace
  2. RAL 4 Furnace
  3. Low temperature furnace

Furnaces are controlled via a temperature controller (e.g. Eurotherm), so nothing on the furnace itself for IBEX to control.

Note: McLennan

see Collimator note

GEM SECI Configs

Document information about GEM SECI configs here.

Configuration Name Sub-Configurations Last Accessed Required
gem_heliox.conf - 14/11/2016 -
gem_sample_changer_matt.conf Choppers 20/05/2016 -
gem_ccr_matt.conf Choppers 28/04/2016 -
gem_sample_changer_Alex.conf Choppers 24/02/2016 -
gem_lowT_furnace_matt.conf Choppers 04/12/2015 -
gem_kelvinox_matt.conf - 01/10/2015 -
GEM_CRYOSTAT.conf Choppers 24/07/2015 -
gem_furnace_matt.conf Choppers, Furnace Pressure 15/06/2015 -
gem_polaris_sample_changer_matt.conf Choppers 26/04/2015 -
gem_furnace_ramp.conf Furnace Pressure 03/04/2015 -
gem_furnace.conf Furnace Pressure 02/04/2015 -
gem_3eurotherms.conf - 20/03/2015 -
gem_sample_changer.conf Choppers 18/03/2015 -
GEM_CRYOSTAT_matt.conf - 02/06/2014 -
gem_ccr.conf Choppers 02/04/2014 -
gem_8t cryo.conf GEM_Base, Choppers 18/12/2013 -
5 Axis.conf - 20/07/2013 -
gem_sample_changer_+_3_Eurotherms.conf 3_Eurotherms 18/03/2013 -
gem_tizrcell_matt.conf - 16/10/2012 -
gem_3eurotherms_pressure.conf - 12/10/2012 -
gem_ambient.conf - 04/10/2011 -
gem_3eurotherms_baritron.conf - 16/04/2011 -
gem_express.conf - 23/02/2011 -
gem_gazcell.conf - 16/02/2011 -
gem_cryo + eurotherm.conf - 15/02/2011 -
gem_7t cryomagnet.conf - 15/02/2011 -
Dave.conf - 15/02/2011 -
gem_kelvinox.conf - 27/01/2011 -
gem_cryo + ilm.conf - 27/01/2011 -
gem_cryo + ilm + SC.conf - 27/01/2011 -
gem_cryo + heliox.conf - 27/01/2011 -
gem_8t cryo + rotation.conf - 27/01/2011 -
gem_8t cryo + kelvinox.conf - 27/01/2011 -
gem_10t cryomagnet.conf - 27/01/2011 -

GEM Genie Scripts

Similarly, Document information about GEM SECI Genie scripts here.

GEM Notes

Add any notes about special items of equipment, setup or conditions on GEM that might impact the deployment and configuration of IBEX.