User Manual
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This temperature rise does not occur when the instrument is connected to a wall outlet or when it is powered by batteries.
Do not connect the C.A 1821 or the C.A 1822 to a PC to make measurements. Use this connection only to program the
instrument or to transfer records.
5.2.3. RESPONSE TIME
The response time is the time at the end of which the e.m.f. reaches 63% of its total variation when the thermocouple is subjected
to a temperature step.
The response time of the sensor depends on the heat capacity of the medium and on the thermal conductivity of the sensor. The
response time of a thermocouple of which the thermal conductivity is good, immersed in a medium having a high heat capacity,
will be short. On the other hand, in a thermally unfavourable medium (such as still air), the true response time may be as much as
100 times that of the thermocouple, or even more.
The values specied in the table below were established in the following conditions:
For the surface, exible, and pipe sensors, by contact with a polished stainless steel plate coated with silicone grease.
For the air sensors, in moving air (1m/s).
For the other sensors, immersed in moving water at 90°C (speed: 0.3 to 0.5m/s).
The temperature ranges given for each type of sensor assume use in a chemically neutral medium.
Using these sensors in a corrosive medium may substantially shorten their lives or limit their measurement ranges.
Designation Measurement range Minimum response time Length
Sensor without handle
SK1 needle -50 to +800°C 1 s 15 cm
SK2 deformable -50 to +1000°C 2 s 1 m
SK3 semi-rigid -50 to +1000°C 6 s 50 cm
SK4 surface 0 to +250°C 1 s 15 cm
SK5 surface with spring -50 to +500°C 1 s 15 cm
SK6 exible -50 to +285°C Contact:1s, air: 3s 1 m
SK7 air -50 to +250°C 5 s 15 cm
SK8 pipe -50 to +140°C 10 s 32 cm
SK19 surface with magnet -50 to +200°C 7 s 1 m
Sensors with handle and extensible spiral cord
SK11 needle -50 to +600°C 12 s 13 cm
SK13 general purpose -50 to +1100°C 12 s 30 cm
SK14 bent surface -50 to +450°C 8 s 13 cm
SK15 surface with spring -50 to +900°C 2 s 13 cm
SK17 air -50 to +600°C 3 s 13 cm
5.3. ELECTRICAL CHARACTERISTICS FOR THE C.A 1823
5.3.1. TEMPERATURE MEASUREMENTS
Temperature sensor PT100 or PT1000
Specied measurement range - 100 to + 400°C -148 to + 752°F
Resolution Display in °C: 0.1°C Display in °F: 0.1°F
Intrinsic uncertainty ± (0,4% R ± 0,3°C)
To determine the total intrinsic uncertainty, add the intrinsic uncertainty of the platinum probe to that of the instrument, given in
the table above.