## page was renamed from InstrumentControl/Cryo
= Cryo-system control =
There are four cold mirrors in KAGRA, two at the center and one each at the end of the 3km tunnels.

Each cold mirror is installed in a cryostat. Each cryostat has 4 cryocoolers. Each cryocooler is powered by a compressor.

== Compressor ==
[[attachment:F70manual-in-english.pdf|Manual]] p54-55

We use the diagnostic interface connector. The pin-out is listed in Table 1 of p54 (p50 at the bottom of the page).

We will use pin #10 and #14 to #20.

There will be four compressors per cryostat. Therefore, the total number of compressors is 16.

== Temperature Sensors ==
We will have 64 temperature sensors per cryostat. There are 4 cryostats. Therefore the total number of the temperature sensors is 256. Each temperature sensor has a differential voltage output. The voltage range is 0-2V for diode sensors (43 sensors out of 64). !PtCo sensors have 0-150mV range (21 sensors out of 64).