Desin Instruments HS-7000 Series, Общее руководство по инструкции

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PSYCHROMETRIC %RH INDICATOR
Using the analog inputs AI 1 and AI 2 as three wire Pt 100 inputs, corresponding to the
temperature measurement of the dry and wet bulbs respectively, from 0 to 50 ºC. In addition
to Pt100 signals, also 0...4-20 mA signals can be used.
In any case, it is very important to use a very high accurate sensors, in a way that, no
differences should be found between them at the same temperature, in a range from 0 to 50
ºC.
The analog input AI 3 can be used to measure another variable or for remote setpoint SP, Alarm,
PID, etc.
Once the two PT 100 probes are connected, check that when set close to each other at the
same temperature, the indicator indicates 100 %RH. If not, select more accurate sensors or
check sensor cables are not introducing errors to the measurement, which can be corrected
by the Tare function of the input signal.
NOTE: The HS-7000 Series can be supplied under demand, with a special option for the
psychrometric calculation between o and 100ºC, where, in addition to %RH Relative Humidity,
Absolute Humidity (%AH) Dew Point and Enthalpy can be calculated.
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Parameterization
The indicator HS-7200 operating as Hygrometer, has no parameter to modify during the
measuring process, except during the configuration procedure.
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Configuration
The programming is realized by linking the inputs AI 1 and AI 2 (Dry temp. and wet temp.
respectively) to the inputs A and B to any Aritmetic Function Block ART, linking its output to
input U of the Display Block DISP, and selecting the «formula 10» correspondent to basic
psychrometric calculation of dry and wet bulbs temperature.
The Display can be configured to indicate %RH in the Upper dispaly ‘U’, Dry Bulb Temperature
in the Middle display ‘M’ and the Wet Bulb Temperature in the Lower display ‘L’, thus, there
is no need to change the loop. Also, each measurement can be programmed to each loop and
shift the loops using
key.
Programming and configuration of these options should be done by LoopWin software (see
Advanced Programming).