1. ComCam Utilities Travis Lange Scott Newbry Camera I&T Mar. 6, 2017

2. Purpose
Define the Interface between SLAC and Tucson
ICD for UT to ComCam Sled (Mechanical)
Identify Components Required to Operate ComCam
Refrigeration Pathfinder with ComCam
Preliminary Design for UT

3. ComCam Utility Requirements
From LTS-508
LTS : 1000mm x 500mm x 500mm max. envelope
LTS : Total mass of utility box < 200kg (including support structure)
Goals and Derived Requirements
Use common hardware with camera UT
Limit use of components with LEDs or displays (and/or make box light-tight)
ComCam shall release no more than 200W heat load into TMA plenum during operations (from Camera spec)
ComCam Utility Box exterior surfaces follow dome air temp to ±5°C
This requirement is ±1°C for the cryostat region

4. Mechanical Interface Utility Box and ComCam Sled
Volume for Utility Box and Refrigeration Pathfinder is same as Camera UT
Ø980mm x 1794mm
Design will feature plate that mounts to ComCam sled similar to Camera UT
Use of wobble plate to manage utility lines entering ComCam Utility Box is undecided
Space for utilities and refrigeration pathfinder

5. Components in Utility Box—Block Diagram

6. Components in Utility Box—Missing Items
Utility Box will also have all components needed to operate Refrigeration Pathfinder
Power supply for heat loads
Pressure transducers
Thermocouple digitizers
HCU to control refrigeration pathfinder
Vacuum pumps/controllers
Scope of utilities needed for refrigeration pathfinder not fully identified

7. Temperature Control

8. Sources of Heat for ComCam
Utility Box (power dissipated)
500W Power Supply (100W)
Cryotel Power Supply (3x 96W)
HCU’s (2x 41W)
Miscellaneous (130W)
Approx. 600W total
All components will be thermally controlled with heat exchangers using dynalene
Cryostat (power dissipated)
Cryotel (3x 480W)
Turbo Pump (450W)
Scroll Pump (220W)
Ion Pump (21W)
Filter Changer
Bonn Shutter
Cryotel will use liquid cooling (dynalene) to remove heat
Turbo/Scroll pump are off during operations
Ion pump is a steady state source of heat at 21W
Much less than 200W requirement

9. Sources of Heat for ComCam
Some heat sources are not mitigated
Scroll pump and turbo pump heat (670W) will be released to dome via conduction/convection during start up
Radiation shield could improve radiation to dome
Liquid cooling of turbo pump would reduce most of transient heat load to environment (is this necessary or a good idea?)
Shutter power dissipation
Filter Changer power dissipation

10. Cryostat Layout
Credit: Justine Haupt

11. Remaining Work Prior to PDR

12. Lots to do
Complete block diagram that includes components required for refrigeration pathfinder
Define the interface between pathfinder/utility box structure and ComCam sled
Allocate space/interface for pathfinder and utility box
Create a layout of components in utility box