Ahlborn ALMEMO 2490-1, Руководство по эксплуатации

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Sensor adjustment
● Conductivity probe must be withdrawn from the liquid and dried.
● O
2
probe for water must be held in a zero solution.
Zero-point adjustment is performed in 2 steps :
The 1st time key
CLR
is pressed the setpoint flashes in the display.
The 2nd time key
CLR
is pressed, adjustment is performed.
To cancel adjustment press key
M
▲
3. Gain adjustment
For gain adjustment the gain calibration resources must be provided
(see Table). Gain adjustment is then performed by pressing key
CLR
in
exactly the same way as for zero-point adjustment.
If correction val. have been programmed, the CORR arrow lights up.
4. Deleting adjustment values
Adjustment values can be cleared by pressing and holding down the key
CLR
. On pH probes you can thus restore the default values, base value
7.00 and gain -0.1689.
Temperature compensation
On conductivity probes and O
2
probes with an integrated temperature sensor
temperature compensation is performed automatically. For pH probes a tem-
perature sensor can be specially configured for this purpose; (see Man. 6.2.6).
10.6 Differential measurement
On version 2490-2, if two sensors with the same units and same decimal point
position are connected at measuring points M0 and M1, the difference M1 - M0
appears automatically below the measuring point M2. The sensors are electric-
ally isolated by means of photovoltaic relays. If the differential channel is not
required, it must be cleared via the interface. If further differential channels are
needed, these can also be created via the interface using the appropriate refer-
ence channels; (see Manual, Section 6.3.4).
11. OUTPUTS
The following interfaces corresponding accessories or options either are ne-
cessary. (see 14.2).
11.1 Interface
The ALMEMO
®
2490 version with the interface can not only be completely pro-
grammed via the computer thus enabling the user to read out all acquired data
(see Manual Ch 6) but also be networked together very easily thus enabling the
user to centrally acquire and record measured values from several measuring
instruments - even if these are located far apart (see Manual 5.3) . The data
cables required for this purpose (see Manual 5.2) are plugged into socket A1.
The baud rate for all data cables is is programmed on leaving the factory to
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