Ahlborn ALMEMO 2490-1, Operating Instructions Manual

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Sensor supply
volt sensor supply voltage available (maximum 150 mA) (self-healing fuse, 500
mA). Other voltages (12, 15, or 24 V or references for a potentiometer and
strain gauge) can be obtained using special connectors;
(see Manual 4.2.5 and
4.2.6) .
7.5 Switching ON / OFF, reinitialization
To switch the device ON briefly press and release the key
ON OFF r
(6) in the
middle of the keypad; to switch the device OFF press and hold down the key
ON OFF r
. After the device is switched off all saved values and settings are re-
tained intact; (see 7.6).
If interference (e.g. electrostatic) or a malfunction (e.g. battery failure) causes
the device to behave abnormally, the device can be reinitialized. To activate
RESET press and hold down the key
CLR r
when switching on. This will restore
all settings - except the device designation - to the factory default status. Only
the programming of the sensors in the ALMEMO ® connectors remains unaf-
fected.
7.6 Data buffering
The sensor's programming is stored in the EEPROM on the sensor connector
and the device's calibration and programmed parameters are stored in the EE-
PROM on the instrument itself, both on a fail-safe basis. Date and time-of-day
are retained intact if the device is just switched off but are lost when the batter-
ies are replaced.
8. CONNECTING THE TRANSDUCERS
Virtually any ALMEMO
®
sensor can be connected to ALMEMO
®
input socket
M0 (and / or M1 on version 2490-2) on the measuring instrument (1). To con-
nect your own existing sensors you simply need the appropriate ALMEMO
®
connector.
8.1 Transducers
The ALMEMO
®
Manual includes detailed descriptions of the comprehensive
ALMEMO
®
range of sensors (see Manual Ch 3) and instructions for connecting
your own existing sensors to ALMEMO
®
instruments (see Manual Ch 4). All
standard sensors with an ALMEMO
®
connector usually have the measuring
range and units already programmed and can thus be connected to any input
socket without further adjustment. A mechanical coding system ensures that
sensors and output modules can only be connected to the correct sockets. All
ALMEMO
®
connectors incorporate two snap-lock levers; these snap into posi-
tion as soon as the connector is inserted into the socket, thus preventing unin-
tended disconnection if the cable is accidentally pulled. To withdraw the
connector, both these levers must be pressed in at the sides.
For the ALMEMO
®
2490 version with the optional seal new specially designed
sensors are available with spray-coated ALMEMO
®
connectors incorporating a
ALMEMO ® 2490 15