Subsections

• • Detector temperature
  • EEU temperature

B.1 Temperature Sensors

Detector temperature

To convert ERD voltage to actual detector temperature one should apply the following relationship:

$$T = B \frac {1} {~^{10}{\rm log}(R_s)+ {\frac {K} {~^{10}{\rm log}(R_s)}} - A}~~~~~~~[{\rm K}]$$ (B.1)

where:

  A, B, K = constants, different for each sensor

  $R_s$ = sensor resistance in $\Omega$, according to

  

$${\rm\frac{R_s}{1000} = \frac{1}{\frac{1}{C_1 {\times} tmd - C_2}-\frac{1}{R_p}} -R_k}~~~~~~~~[\Omega]$$ (B.2)

Where:

  tmd = telemetry data value

  $C_1, C_2$ = constants

  $R_k$ = harness resistance in k${\Omega}$

  $R_p$ = EEU shunt resistor in parallel to sensor in k${\Omega}$

  

Table B.1: Constants for PHT temperature sensors.

Sensor	A	B	K
FCS1	6.54	2.90	10.67
FCS2	6.54	2.90	10.67
C100	5.44	3.05	7.34
C200	4.51	3.12	4.92
P1	6.02	3.61	8.77
P2	7.59	3.13	14.40
P3	5.11	3.49	6.29
S1	6.54	2.94	10.66
S2	6.54	2.90	10.67

Table B.2: Resistances for PHT temperature sensors.

Sensor	$C_1$ [k$\Omega$]	$C_2$ [k$\Omega$]	$R_k$ [k$\Omega$]	$R_p$ [k$\Omega$]
FCS1	0.259	495.83	1.12	1000
FCS2	0.256	495.83	1.12	1000
C100	0.099	146.38	1.34	infinite
C200	0.048	$-$78.32	0.67	infinite
P1	0.174	344.55	1.12	499
P2	0.210	388.13	1.34	499
P3	0.182	288.11	1.34	infinite
S1	0.173	341.63	1.12	499
S2	0.170	336.88	1.12	499

EEU temperature

$$T = \frac{B}{A+ln(R_s)} ~~~~~~~~~~~~~~~~~~[{\rm K}]$$ (B.3)

with

$$R_s = \frac{tmd-2048}{4096-tmd} \times 7500~~~~~~~~~~~~~~~~~~~[\Omega]$$ (B.4)

where

A =	3.9489
B =	3442 K
R$_s$ =    sensor resistance in $\Omega$
T =	EEU Temperature in K
tmd =	telemetry data value