Gonnheimer Elektronic DC 155, Руководство пользователя

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Page 10 4 manual DC155
Gönnheimer Elektronic GmbH phone.: +49 (6321) 49919-0, fax: -41 Email: info@goennheimer.de
2.5 Temperature compensation (requires Pt100- option)
Any fluid has a specific expansion coefficient
γ
. The volume of the fluid increases with its temperature.
Using a volume measurement sensor for a mass dosing application, introduces an inaccuracy into the dosing
process, if the temperature is not taken into account.
The DC155 can compensate the thermal expansion of a fluid according to the following formula:
! " = ! #1 + % " − " &
V( ϑ ) volume at actual temperature
V
0
volume at reference temperature
ϑ
actual fluid temperature
ϑ
0
reference temperature
γ
expansion coefficient
The DC155 measures the temperature of the fluid with a Pt100 temperature sensor. The user can set the
values of the expansion coefficient and the reference temperature with the "Temperature compensation"
menu.
The signs of the temperature values are entered by using the arrow keys . The left arrow sets a negative sign,
the right arrow sets a positive sign.
The temperature measurement value can be monitored. This allows to recognise broken wires and short cuts of
the Pt100 wiring. The DC155 uses a default value, if the Pt100 temperature is outside the configured temperature
range, given by the parameters "Minimum Value" and "Maximum Value". The dosing process can either be
stopped or continued in that case. Additionally, it is possible to activate any digital output whose functionality has
been set to "Any failure".
Temperature Compensation
0. Temperature compensation: active
1. Reference temperature: 20°C
2. Coeff. of expansion: 0.100E-3 1/K
3. Temperature monitoring: Yes
4. Minimum value: -10°C
5. Maximum value: 50 °C
6. Default value: 20°C
7. Stop Dosing: Yes
8. Error signal: Yes
.
End