Mosaics put tough requirements on temperature control and housekeeping functions. Thus far, ESO has used PULPO  for this purpose. 33 units have been built for 16 instruments, but contemporary mosaics, like ESO's OmegaCAM  with 36 CCDs in the focal plane, require a new approach [2,3]. For this reason, ESO has developed a new housekeeping unit, PULPO 2 (see Fig. 1) .
Key features of PULPO 2 are:
• Monitoring of 29 PT100 sensors (4 wire system) by default and up to 125 with external multiplexer boards.
• Temperature control of the focal plane with up to 8 independent heaters.
• Monitoring of the vacuum in the cryostat (by means of Balzers or Edwards vacuum gauges).
• Separate alarm outputs for temperature and vacuum.
• Shutter handling with control of the exposure time and measurement of open and close delays.
• Internal logging of numerous system parameters over time (up to 65000 records), thereby making PULPO 2 a valuable trouble shooting and optimizing tool.
• Backward compatibility with PULPO.
The PULPO 2 control software exploits all capabilities of the hardware to implement further functionality for system monitoring and recovery to a safe state in case of failure.
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