Preparing UltraDAS in an instrument change

This page is part of the ING manual INS-DAS-29 Operations manual for UltraDAS.

Equipment to be mounted on the telescope


The CCD plus its controller must be mounted on the appropriate camera of the spectrograph. The CCD controller is mounted to the instrument independently of the cryostat.

When putting a CCD plus controller on the 235 camera of IDS, the lifting is much easier if the mounting flange is vertical. Slew the telescope in declination to about 30 degrees North.

The power supply (grey box) and shutter electronics for UltraDAS are in a separate rack. Normally, they are mounted in the same rack as the Cassegrain terminal-server.


All the CCD-control equipment of the WFC is mounted on the instrument's frame. This equipment should be assembled on the frame before the instrument is put on the telescope.

The CCD controller is mounted to the cryostat with a set of hoops. The controller should be at the top when the WFC is on its handling trolley.

The PSU for the CCD controller is mounted on the instrument's frame. It is at the left-hand side when the instrument is on its trolley.

Cabling for the CCDs is in the main loom that passes through the WFC's mast and across the west arm of the spider.


The cryostat mounts on to UES in the traditional way. The detector controller for WHTWFC is not mounted onto the cryostat; it can be rested on top of the UES casing next to the cryostat and needs no restraints. The rack with the PSU and shutter controller can also be rested on top of UES' case.


The cryostat mounts on to PFIP in the traditional way.

The detector controller is bolted directly to the instrument frame, to the side of the cryostat.

The shutter controller and PSU are held in a casing that mounts on top of the detector controller, with the shutter controller's indicator lamps showing at end furthest from the telescope's primary.


At the instrument

The cable for  clocks and pixel-value signals connects to boards inside the controller and emerges from the CCD-controller through the gap in the front panel of the controller box. This cable runs to the multi-pin connector on the side of the cryostat. This connection should only be made or broken in static-free surroundings, before the cryostat is brought to the telescope.

Cable from the temperature port on the controller front panel to temperature port on the cryostat. This cable carries telemetry from the cryostat to the controller and allows the controller to raise the cryostat's temperature to its working value by operating a heater inside the cryostat.

Cable from the ID port on the  controller front panel to the ID plug on the outside of the cryostat. This cable allows the DAS to sense which controller is connected. If the ID cable is left off, the DAS will refuse to drive the camera.

Cable from the shutter-control port on the controller front panel to the socket marked "from SDSU" on the shutter-control rack. This allows the controller to command the shutter and to sense the shutter's position. The INT WFC does not have this cable, because the shutter is driven by the ICS.

Cable from the socket marked "to shutter" on the shutter-electronics rack to the shutter on the instrument body. The connection at the instrument end varies:

Cable from the detector controller's PSU to the controller itself. Note that there are two different types of PSU and they are matched to power-conditioning boards in the controller. The cables for the two PSUs are different.

Supply mains power  (240V 50Hz AC) to the dector controller's PSU and (separately) to the shutter controller.

Attach fibre optic connections (one pair) from the DAS to the detector controller. At the controller, the fibres and sockets are each marked "To CCDC" or "from CCDC"; match the labels on the cables and sockets. (Swapping over the fibres in the pair disables the controller.) At the other end of htis first fibre-segment, the arrangements vary.

At the DAS

Fibre-optic connections must be made in the room where the DAS computer is kept.

In the INT:

At the WHT:

Configuration files

UltraDAS uses configuration files to define certain behaviours of the system. The files are described in detail in  INS-DAS-25.

When changing to camera CCC with instrument III on computer NNN say, then UltraDAS must be able to see the following files:

Configuring the VAX ICS on the WHT

The ADAM system on the VAXen traditionally contains parts of a data-acquisition system. Those features are not used with UltraDAS and must be turned off.
  1. Log in to the ICS computer as observer.
  2. When asked "do you want to run the observing system?", answer yes.
  3. Run confedit.
  4. In the configuration file displayed by confedit, find the section describing the detector options.
  5. Add (or enable, by removing the comment marker from the start of the line) the option for which the "detector" is SDSU; comment out the current option by puting an exclamation mark at the start of the line.
  6. Exit from confedit.
This setting is permanent; it will persist across restarts of ICL. When you want to use the instrument in question with the ADAM DAS, run confedit as above and reverse the changes.