THERMAL ISSUES (hot stuff...)

Last updated Sept 1st, 2000

 

TEMPERATURE SENSORS LOCATION AND LIST

See drawing CH2917.C001

On February 9th, we have replaced the old temp4m PC with the new Labview-based system. The data is accessed by typing 'temp4m' from any machine. That will show you the important fields logged in /ut02/seeing/temper/newtemp.log which are described below:

1

2

3 = A

4 = B

5 = C

6 = D

7 = E

8 = F

9 = G

10 = H

UT time

UT date

Lo tru NW

Lo tru NE

Lo tru E

Lo tru W

Up tru N

Up tru E

Up tru S

Up tru W

11 = I

12 = J

13 = K

14 = L

15 = M

16 = N

17 = O

18 = P

19 = Q

20 = R

unused

Mirror glycol

Mc air out

Oil pump

Low dome

Oil bef pad

Oil aft pad

High dome

PF cage

Cass cage out

21 = S

22 = T

23 = U

24 = V

25 = W

26 = X

27 = Y

28 = Z

29 = a

30 = b

Mirror W

Chimney

Mirror N

Mirror E

Mirror S

outside

Dome floor

Oil glycol

Dome RH

Oil volt read

31 = c

32 = d

33 = e

34 = f

35 = g

36 = h

37

38

39

40

MC volt read

Oil pump status

Cass cage in

air M1 cell

air above M1

guider air

dew point

oil volt calc

mc volt calc

  

Notes:

  • the letters are the addresses of the DGHs
  • Mc stands for "mirror cooler"
  • 35 and 36 added on 31Aug00
  • Since 04/nov/99, both temperature logs (the old one 'temp.log' and the new one) read UT time (instead of local time before).

     

    SOME QUICK CHECKS THAT THE THERMAL SYSTEM IS WORKING!!

    Typing "temp4m" on a Sun machine gives a list of temperature:

    See drawing CH2890-A001 for mirror cooler details.

    MIRROR COOLER:

    OIL:

    DOME and TEL:

     

    GLYCOL SYSTEM:

     

    Notes about the old 'temp.log':

    a- On 04/Nov/99, we found out errors in field labels in temp.log:

    b- On 04/nov/99, we modified the labels on the old temp4m PC display and swap connectors at the multiplexer input in order to have the PC algorithm use the correct sensors and log a trustful temp.log as indicated in the table above.

    c- the old grey relay box in the Cass cage has the following inputs for the mirror sensors: #1 with cable labeled north, #2 with east, #3 with south and #4 with west. DO NOT change that!

    d- the values displayed by the multiplexer in Tolnet show small variations (+/- 1) from the reality (due to sensor calibration, effects of the cables,...) and serves only for debugging. The old PC algorithm uses a correction table for each sensor (file "tcoef").