E+E Elektronik HTS801, Руководство пользователя

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User Manual HTS801
Humidity and Temperature Sensor for High Humidity and Chemically Polluted Conditions | 10
3.4 Operation and Heating Modes
3.4.1. Overview Operation Modes and Types
Operating Mode HTS801 Type Use in environments with Function Trigger
Condensation Guard (CG) T5 / T9 / T10 Temporary condensation RH setpoint
1)
High Humidity Guard (H
2
G) T7 / T17 / T28
Continous high humidity and
condensation
Always on
1) Factory setting: acc. to ordering guide
3.4.2. Automatic ReCovery (ARC) against Chemical Pollution
When capacitive humidity sensing elements are exposed to chemical pollution (e.g. detergent residues), the presence
of foreign molecules can distort the measurement reading of the sensor. With the ARC function foreign molecules
can be evaporated from the sensing element by brief and intensive heating.
All HTS801 types support the ARC function.
PLEASE NOTE
Before a recalibration is done after an ARC cycle, reconditioning of the sensing element is recommended.
For best reconditioning, please allow 2 free calibration cycles between 15 %RH and 90 %RH in steps of
~20 %RH and 20 min stabilisation time.
The start of the ARC function can be triggered as follows:
Manual: by using PCS10 or via display and push-buttons. A manual start of the ARC function is recommended when
▪.
chemical.pollution.on.the.sensing.element.is.expected.(cleaning/sterilization).
▪.
measurement readings deviate significantly from a calibration reference.
Cyclic: by using PCS10 or order code option ARC1 (24 h), ARC can be configured to start periodically at a
certain time interval.
The cyclic option can be extended to include an automatic start at power on. This function can be switched on
and off via PCS10, display and push-buttons or using order code option ARC2 (24 h power on).
Periodic heating shall be used to minimize drift effects in applications with high chemical pollution. The ideal cycle
time depends on the type of pollution and its concentration and has to be determined empirically.
heating
time
cool-down
time
freezing
heating 1 heating 2
definable interval time
T [°C]
T [°F]
t [min]
Fig. 4 ARC cycle
External: by using the optional ARC module the function can be activated using an external signal see chapter
3.5.3. ARC Module (Option AM1). RS485 or Ethernet with Modbus commands can be used to start ARC as well.