Power Supply; Battery Operation And; Mains Operation; External Dc Voltage Supply - Ahlborn ALMEMO 2490-1A Operating Instructions Manual

POWER SUPPLY

7.
Power can be supplied to the measuring instrument in any of the following ways
: 3 AA alkaline batteries (included in delivery)
Mains adapter 12V, min. 1 A with ALMEMO
Electrically isolated power supply cable (12 VDC, 0.25 A)
12V DC clamp connector to socket DC
Our product spectrum includes all the appropriate accessories.

7.1 Battery operation and

Power is supplied to the measuring instrument as delivered by 3 AA batteries.
At a current consumption of approx. 16 mA the operating time will be approx.
150 hours. The current operating voltage is displayed each time the the device
is switched on; this gives you a basis for estimating the remaining operating
time. When the remaining battery capacity drops to approx. 10 percent, the LO-
BAT arrow will appear in the display. If the batteries are completely discharged
the device will switch off. To replace old batteries first unscrew the battery com-
partment cover (7) on the rear of the device.

7.2 Mains operation

The ALMEMO ® 2490A can be supplied with power from an external source pref-
erably using mains adapter ZA 1312-NAx (12 V / min. 1 A) via the DC socket (4).
Please ensure that the mains voltage is correct.

7.3 External DC voltage supply

The DC socket (4) can also be used to connect DC voltage, 12 V (minimum 200
mA). This is via an ALMEMO
supply has to be electrically isolated from the transducers, then is needed electri-
cally isolated supply cable ZA 2690-UK must be used. It will then be possible to
use the measuring instrument in a 12-volt or 24-volt on-board supply system.

7.4 Sensor supply

At the terminals + (plus) and – (minus) in the ALMEMO
for battery operation and 12V for mains operation sensor supply voltage availa-
ble (maximum 400 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,

To switch the device ON briefly press and release the key
middle of the keypad; to switch the device OFF press and hold down the key
. After the device is switched off all saved values and settings are retained
OFFr
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 RE-
SET press and hold down the key
settings - except the device designation - to the factory default status. Only the
programming of the sensors in the ALMEMO
14
® connector (ZA1000-FSV). If, however, the power
CLR r
when switching on. This will restore all
®
connector
®
® connector there is a 9V
ON
connectors remains unaffected.
ZA1312-NAx
ZA2690-UK
ZA1000-FSV
(6) in the
OFFr
ON