Thermo Scientific 3403 Manual page 49

Thermo Scientific
Table 7-5. Probe Temperatures
Probe Temperature *
20°C
25°C
30°C
35°C
37°C
40°C
* 1000Ω Platinum Resistance Temperature Detector (PRTD)
IEC 751, DIN EN 60751 grade platinum (α = 0.00385 Ω/Ω/°C)
Tolerance IEC standard 751 class B, Δt = ± [(0.30) + 0.005 x |t|]
TP14 "AC Mon"
Only used on units with an O2 sensor. O2 sensors used in this applica-
tion utilize a capillary technology to quantify O2 concentrations. In
very simplified terms, this sensor is analogous to a battery whose charge
level is dependent on the presence of O2. The more O2, the higher the
charge or voltage produced. In ambient conditions, the concentration of
O2 is 20.9%. Off the shelf, the O2 sensor will produce 7-14mV. This
off the shelf value is particular to each sensor and will be tied to 20.9%.
The slope for the sensor is thereby determined by the off the shelf value
and 0mV equating to 0%. For instance, if a sensor produces 10.45mV
off the shelf, it will have a slope of 0.5mV / % O2 (10.45mV/20.9%).
This value can be viewed and/or reset in the service loop of the incuba-
tor. With this value it is straightforward to check a measurement at
TP14 against the displayed percentage. In addition, the sensor is a
stand-alone device - the voltage can be checked at the sensor's molex
connector with it completely out of circuit.
RTD Value
1077.928 ˜
1097.337 ˜
1116.718 ˜
1136.069 ˜
1143.802 ˜
1155.392 ˜
Section 8
Appendices
Test Point
100.89 mV
102.67 mV
104.44 mV
106.21 mV
106.91 mV
107.97 mV
Midi 40 CO2 Incubator 8-17