Campbell Manufacturing TEMPERATURE PROBE 109SS Manuale Utente
Model 109SS Temperature Probe
1: Excite-Delay (SE) (P4)
1: 1
1: 1
Reps
2: 25
2500 mV 60 Hz Rejection Range (Delay must be zero)
3: 1
SE
Channel
4: 1
Excite all reps w/Exchan 1
5: 2
Delay (0.01 sec units)
6: 2500
mV
Excitation
7: 3
Loc [V_Vx ]
8: .0004
Multiplier
9: 0.0
Offset
6. Measurement Details
Understanding the details in this section are not necessary for general
operation of the 109SS Probe with CSI's dataloggers.
operation of the 109SS Probe with CSI's dataloggers.
The Therm109 Instruction outputs a 2500 mV excitation and measures the
voltage across the 24.9 K resistor (Figure 6-1). The thermistor resistance
changes with temperature.
voltage across the 24.9 K resistor (Figure 6-1). The thermistor resistance
changes with temperature.
EX
HI
AG
G
BLACK
RED
PURPLE
CLEAR
24.9K
Ω, 0.1%
10K3AI
THERMISTOR
FIGURE 6-1. 109SS Thermistor Probe Schematic
The measured voltage, V, is:
t
EX
R
V
V
+
=
900
,
24
900
,
24
Where V
EX
is the excitation voltage, 24,900 ohms is the resistance of the fixed
resistor and R
t
is the resistance of the thermistor
10