Function Range of the ALMEMO 2890-8
5.1.1 Sensor Programming
The measuring channels are automatically programmed by the ALMEMO
®
connectors. However, the user can easily complete or modify the programming
via keyboard or via interface.
Measuring Ranges
There are corresponding measuring ranges for sensors with a non-linear char-
acteristic such as 10 thermocouple types, Ntc and Pt100 sensors, infrared sen-
sors, and flow sensors (rotating vanes, thermoanemometers, pitot tubes).
Humidity sensors are available with function channels that also calculate hu-
midity data such as dew point, mixture ratio, vapour pressure and enthalpy.
Even complex chemical sensors can be used. The acquisition of measured
data from other sensors is easily possible by using the voltage, current and re-
sistance ranges with individual scaling in the connector. Existing sensors can
be used without problems. Only the corresponding ALMEMO
®
connector has
to be connected using its terminals. Furthermore, there are adapter connectors
with an own microcontroller for digital signals and for measuring frequencies
and pulses. This way, nearly all sensors can be connected to any ALMEMO
®
measuring instrument and are interchangeable without requiring any settings.
Function Channels
Maximum, minimum, average values and differences of certain measuring
junctions can be programmed as function channels, also in device internal
channels, and can be processed and printed like normal measuring junctions.
Furthermore, function channels for special measuring tasks are provided to de-
termine the temperature coefficient Q/
D
T and wet bulb globe temperature.
Dimension
The 2 digit dimension can be altered for each measuring channel so that the
display and the printout will always indicate the correct dimension, for example
when a transmitter is connected. The conversion from °C to °F is automatically
performed according to the dimension.
Name of Measured Values
For identification of the sensors a 10-digit alphanumeric name is provided. It is
entered via the keypad or the interface and appears on the display, the printout
or the computer display.
Correction of Measured Values
For correcting measured values a zero point and slope correction can be ap-
plied to the measured value of each measuring channel. This also allows for
sensors to be interchanged that usually, at first, require an adjustment (expan-
sion, force, pH). The zero point and the slope correction are virtually performed
by the push of a button.
Scaling
The base value and the factor allow for a further scaling of the corrected mea-
sured value of each measuring channel for zero point and slope. The decimal
ALMEMO
®
2890-9
11
