BARTEC BENKE HYGROPHIL H 4230-12 Ex Zone II, Руководство по эксплуатации, Страница: 18 / 112

System description
12
Operating Instructions HYGROPHIL® H 4230-12 BA 060207
1.3.11 Interfaces
Two electrically isolated analogue current outputs are available for the pur-
pose of evaluating and processing the measured values.
You can allocate any humidity measurement variables or auxiliary variables
to these outputs as you wish.
You are free to define the limits of the measurement ranges within the re-
spective overall measurement range as you wish (see section 5.2.1).
The analogue outputs are constantly monitored to ascertain whether the cur-
rent measured value lies within the respective measurement range that has
been programmed. If there are deviations, a fault is reported.
In addition, one of the two analogue current outputs can be monitored to as-
certain whether it adheres to a minimum value and maximum value.
Once they have been switched on, the outputs remain at 0 until the normal
operating conditions are reached.
If a fault is reported during measurement operation, the outputs are fixed at
the value that they had directly before the fault report appeared.
Field bus interface (PROFIBUS DP).
All measured values can also be recorded using the field bus interface. In
addition, the system can be configured using this interface.
1.3.12 Temperature sensors
The internal temperature sensor, T
internal
, is built into the enclosure as a fixed
element.
It is used for compensating the humid temperature.
For measuring temperature-dependent humidity variables (such as relative
humidity (RH) or enthalpy (h)), you have the option of installing an external
temperature sensor (T1
external
). This must be placed in the position where the
humidity variable is to be measured.
1.3.13 Gas sampling hose
The gas humidity is not measured within the respective system. Rather, the
gas is extracted from there and pumped to the HYGROPHIL system via a
connecting line. It is essential that no water vapour condenses within the
connecting line as this would falsify the measurement result and could pos-
sibly lead to operating problems. In order to prevent this, the temperature of
this line (and of the entire suction apparatus) must be kept above the maxi-
mum dew-point temperature to be expected.
To this end, a gas sampling hose is used and its temperature is automatical-
ly kept constant. At the same time, the dry temperature sensor is used as
the actual-value sensor. By programming the dry temperature (TT), there-
fore, you also specify the gas sampling hose temperature.
1.3.14 Connection for external water detector
An external water detector is available as an optional extra for monitoring the
level in the water storage tank.
1.3.15 Filter
HYGROPHIL
®
H 4230 is highly insensitive to dirt. Under certain extreme op-
erating conditions, however, it may make sense to use a filter in order to ex-
tend the maintenance interval for the measuring chamber.
If required, please ask our expert consultants to select a suitable filter.
Field bus interface
Two analogue outputs