5. Introduction
5.4 Sensor programming
Measuring ranges
For Pt100 sensors, two high resolution measuring ranges exist: -200.000 to
560.000°C and (as an option) -200.00 to 850.00°C. The calculation of the hu-
midity variables relative humidity and dew point is rounded to two decimal
places. Additionally, the following humidity variables are available: mixture ratio
MH, r [g/kg], absolute humidity AH, dv [g/m3], vapor pressure VP, e [mbar] and
enthalpy En, h [kJ/kg]. Differential measurements and monitoring of the supply
voltage are possible via further function channels.
Or you can connect and program our latest D6 digital humidity sensors. This
device - unlike standard ALMEMO
®
V6 devices - can even display individual
range abbreviations; these would otherwise have to be transferred via interface
to the PC.
Measured channel designation
Each sensor is identified by means of a 10-character alphanumeric name.
These names are entered via the keypad or the interface and appear in the
display, in the printout, and on the computer screen.
Correction of measured values
The standard functions regarding measured value correction and scaling can-
not be used due to the considerably expanded measuring range. It is however
possible to set the measured value of every measuring channel to zero. More-
over, the sensors are adjustable in several points: either via multi-point lin-
earization i.e. the error curve can be stored in the measurement plug or via
modification of the Pt100 coefficients.
For digital D6 sensors the standard correction functions, zero-point and gain,
are also provided.
All programmed sensor parameters are saved in the connector and are auto-
matically restored as and when a sensor is plugged in.
5.5 Measuring operation
The user can move forwards or backwards from one measuring channel to the
next using the keypad. Data is output on the display at a rate of 1.25 measur-
ing operations per second (mops).
Atmospheric pressure compensation
Humidity variables are heavily dependent on atmospheric pressure. To avoid
errors of this nature the device incorporates its own atmospheric pressure sen-
sor for compensating its measured values. All D6 sensors incorporate their
own atmospheric pressure sensor.
Measured value smoothing
For both measuring channels measured values of an unstable, fluctuating na-
ture can be smoothed by taking a sliding average over a number of values pro-
grammable from 2 to 99. With D6 sensors a separate time constant can be
programmed. (see sensor instructions)
Maximum and minimum values
10 ALMEMO
®
1036
