Telescope Temperature Sensors

Nine (9) temperature sensors PT100 are mounted on various parts of the telescope and are connected to signal conditioners providing a 4-20mA signal output. These signals are connected to a dedicated field interface (ESO supply) for signal formatting before entering the Analog Input ports.
The sensors are monitoring the temperature on the following parts:


The thermal controller PKC from EROELELECTRONIC keeps the Altitude cabinet internal temperature equal to the ambient air temperature. It acts on a motorized valve regulating the coolant flow inside the heat exchanger of the Altitude cabinet. One PT100 senses the ambient air temperature, the other one senses the Altitude cabinet internal air temperature. The LCU has got no control on the regulation but monitors the two temperature sensors connected to the thermal controller PKC:

Telescope Temperature Sensors Interfaces:

The connection layout and pin assignment is given in Annex 1 VLT-DWG-ESO-15154-1769

Item
From
To
Signal
Description
TOP RING SENSOR:
1 ATS LCU Temperature TopRing + Current Loop 4-20mA (-10,+25C)
2 ATS LCU Temperature TopRing -  
3     Shield  
TUBE SENSORS:
4 ATS LCU Temperature Tube A + Current Loop 4-20mA (-10,+25C)
5 ATS LCU Temperature Tube A -  
6     Shield  
7 ATS LCU Temperature Tube B + Current Loop 4-20mA (-10,+25C)
8 ATS LCU Temperature Tube B -  
9     Shield  
FORK SENSORS:
10 ATS LCU Temperature Fork A + Current Loop 4-20mA (-10,+25C)
11 ATS LCU Temperature Fork A -  
12     Shield  
13 ATS LCU Temperature Fork B + Current Loop 4-20mA (-10,+25C)
14 ATS LCU Temperature Fork B -  
15     Shield  
M7 SENSOR:
16 ATS LCU Temperature M7 + Current Loop 4-20mA (-10,+25C)
17 ATS LCU Temperature M7 -  
18     Shield  
M1 SENSORS:
19 ATS LCU Temperature M1 A + Current Loop 4-20mA (-10,+25C)
20 ATS LCU Temperature M1 A -  
21     Shield  
22 ATS LCU Temperature M1 B + Current Loop 4-20mA (-10,+25C)
23 ATS LCU Temperature M1 B -  
24     Shield  
25 ATS LCU Temperature M1 C + Current Loop 4-20mA (-10,+25C)
26 ATS LCU Temperature M1 C -  
27     Shield  
Power Supply:
28 LCU ATS Power Supply + 24VDC / 600mA for the 9 Temperature Sensors PT100 and Signal conditioners
29 LCU ATS Power Supply -  
30     Shield  

Altitude cabinet Thermal controller:

Item
From
To
Signal
Description
COMMUNICATION:
1 ATS LCU Thermal controller Communication RS485 Port to PKC EROELECTRONIC - Protocol details [RD19]
GENERAL COMMANDS:
2 ATS LCU Read temperatures Cabinet Temperature
Ambient Air Temperature

 

Last modified: Thu January 16 03 13:54:55 UTC 2001