Functions; Sensor Programming - Ahlborn ALMEMO 2490-2 Operating Instructions Manual

system; these are described in detail in the ALMEMO
cluded in delivery with each device.
Detailed explanation of the ALMEMO
Overview of the device functions and measuring ranges (Manual Ch 2)
Basic principles, operation, and technical data for all sensors (Manual Ch 3)
Options for connecting your own existing sensors (Manual Ch 4)
All analog and digital output modules (Manual Section 5.1)
Interface modules USB, RS232, optic fiber (Manual Section 5.2)
The whole ALMEMO
All functions and their operation via the interface (Manual Ch 6)
Complete list of interface commands with all the printouts (Manual Ch 7)
The operating instructions you are now reading cover only those features and
controls that are specific to this device. Many sections therefore also refer to
the more detailed description in the Manual; (see Manual, Section xxx).

5.1 Functions

®
The ALMEMO
for all ALMEMO
measuring possibilities are virtually unlimited; there are 4 channels per sensor
connector and 4 device-internal function channels (type -2 only) - with over 70
measuring ranges. For operation purposes the device incorporates a large
LCD display and a keypad. An option is available with an internal electrically
isolated analog output including a DC socket for a mains adapter (socket P0).
The standard version with interface has three output sockets, namely A1 and
A2, suitable for all ALMEMO
faces, trigger and relay cables, plus a DC socket for a mains adapter. Several
devices can be networked by simply linking them together via cable.

5.1.1 Sensor programming

The measuring channels are programmed, completely and automatically, by
®
the ALMEMO connectors. The user can freely supplement or modify this pro-
gramming; this applies to the interface version only. However, devices without
the interface also behave according to all the programmed parameters.
Measuring ranges
Appropriate measuring ranges are available for all sensors with a non-linear
characteristic, e.g. 10 thermocouple types, NTC and PT100 probes, infrared
sensors, and flow transducers (rotating vanes, thermoanemometers, Pitot
tubes). For humidity sensors additional function channels are available for cal-
culating humidity variables such as dew point, mixture ratio, vapor pressure,
and enthalpy. Even complex chemical sensors are supported. Measured val-
ues from other sensors can also be acquired using the voltage, current, and
resistance ranges with individual scaling in the connector. Existing sensors can
also be used - so long as the appropriate ALMEMO
®
networking system (Manual Section 5.3)
2490-1 has one electrically isolated measuring input suitable
®
sensors; the 2490-2 has two such measuring inputs. The
®
output modules, e.g. analog outputs, digital inter-
®
®
system (Manual Ch 1)
®
connector is connected
ALMEMO
Introduction
Manual which is in-
® 2490 9