Monitoring Herschel Telescope Temperatures

We need to monitor the temperature of the Herschel Telescope as it affects the FTS pipeline tasks. This is particularly important during Comissioning and PV phases.

There is a definition of a satellite housekeeping product in the Auxiliary Products Specification. This lists the temperature parameters and details their APID, type and sub-type. Unfortunately the satellite housekeeping product will not be implemented, but PACS are working on an implentation using BinStruct to produce a Trend Analysis product for each operational day.

Herschel Auxiliary Products Specification document (on livelink. See Section 9 on p.25)

In summary, the temperature sensors we need are:

From CCUA

Two source packets are possible, both with TYPE=3, SUBTYPE=25, APID=18 and either PI1=9752 or PI1=22820. In both cases, the corresponding SCOS-2000 packet has SPID=260141999.

M1 temperature	T331 PT1000	TM raw parameter KM253302
M1 temperature	T333 PT1000	TM raw parameter KM254302
M1 temperature	T335 PT1000	TM raw parameter KM255302
M1 temperature	T337 PT1000	TM raw parameter KM256302
M2 temperature	T339 PT1000	TM raw parameter KM257302
M2 temperature	T341 PT1000	TM raw parameter KM258302

From CCUB

Two source packets are possible, both with TYPE=3, SUBTYPE=25, APID=18 and either PI1=10922 or PI1=23600. In both cases, the corresponding SCOS-2000 packet has SPID=260144999.

M1 temperature	T332 PT1000	TM raw parameter KM248303
M1 temperature	T334 PT1000	TM raw parameter KM249303
M1 temperature	T336 PT1000	TM raw parameter KM250303
M1 temperature	T338 PT1000	TM raw parameter KM251303
M1 temperature	T340 PT1000	TM raw parameter KM252303
M2 temperature	T342 PT1000	TM raw parameter KM262303

The positions of these sensors on the mirrors are given in the Herschel/Planck User Manual, Chapter 5, Extra Payload and non SVM Equipment. The following figures and explanation are from Issue 3.2 of this document:

Reading the temperatures

To convert the packets, we need the spacecraft MIB. This should be loaded onto the machines at ESAC that run the SPG, but we don't have it at RAL to test any scripts at the moment. The spacecraft MIB is loaded in SCOS on the PISA machines at the MOC.

What BinStruct is needed for is to apply the conversion and interpret the packets using the spacecraft MIB.

We tested whether these parameters are connected by examining SCOS on the machine at Kourou. This shows that these parameters do contain real temperatures at the moment:

-- EdwardPolehampton - 23 Feb 2009