harps... north harps-n pdr harvard cfa, 06/07-12-2007 thermal enclosure
Post on 21-Dec-2015
215 views
TRANSCRIPT
HARPS ... North
HARPS-N PDR Harvard CfA, 06/07-12-2007
Thermal enclosure
3-level concept
Spectrograph room: +- 0.2 K
Isolation Box: +- 0.01 K
Spectrograph: +- 0.001 K
15°C
17°C
T-sensor
Spectrograph room
Model : YORK YEB 3S
Serial Nr. : 135.157.DN003
Room thermal control
Isolation Box
Temperature control
✓ Lakeshore 331S T-controller + diode sensors + heaters
✓ 60 mm polyurethane panels with 1 mm Al skin
✓ Floor isolated by 100-mm foam ‘carpet’
✓ Thermal load on external room: about 10 W/K
Performances, but ...
Lessons learned
Concept works well and is simple
Changing thermal load through feet produces gradient and seasonal effects
➡ Thermal isolation of feet
➡ Heater below feet, Tref = vacuum vessel e.g. using Lakeshore controller