WIKA CTH6200 - Handbuch (Seite 18)

WIKA Betriebsanleitung Hand-Held Thermometer
2146872 09/2004 GB/D
18
GB
WIKA Operating Instructions Hand-Held Thermometer
Hand-Held Thermometer
CTH 6200
4. General information about temperature sensors
■ Heat loss caused by probe construction:
Especially when measuring temperatures which deviate very
much from the ambient temperature, measuring errors often
occur if the heat loss caused by the probe is not considered.
When measuring fluids therefore the probe should be emerged
sufficiently deep and be stirred continuously. When measuring
gases the probe should also emerge as deep as possible in the
gas to be measured (e.g. when measuring in channel/pipes) and
the gas should flow around the probe at sufficient flow.
The tube length should be selected long enough, that temperature
keeps low at the handle.
■ Self Heating
The measuring current of the instrument is just 0.3 mA. Be-
cause of this comparably low current practically no self heating
effect has to be considered, even at air with low movement
the
self heating is <= 0.01 °C.
■ Cooling by Evaporation
When measuring air temperature the probe has to be dry.
Otherwise the cold due to the evaporation causes too low
measurings.
4.1 Available sensors
The device is designed to be connected to all sensors of the
CTH6200 series (see valid price list CTH6200).
5. The serial interface
By means of the serial interface and a suitable electrically isolated
interface adapter the device can be connected to a computer for
data transfer (USB-adapter on request), to visualise the data with
the WIKA Datalogger evaluation software GSOFT (see valid price
list CTH6200). To avoid transmission errors, there are several
security checks implemented e.g. CRC.