INSTRUCTIONS FOR PRESSURE CALIBRATION OF THE INSTRUMENT
The instrument DO 9709 has an internal pressure sensor.
To calibrate the pressure input, place the instrument near a reference instrument with an accuracy
of at least over 0.5 mbar.
To access the procedure for calibrating the measurement of atmospheric pressure, press the
PROG key repeatedly until you come to program P12.
With P12 on the display, press the ENTER key. The top of the display will show the message PrS,
while the bottom of the display will show the atmospheric pressure currently measured by the
instrument in mbar. The °C and °F symbols are active on the display.
* To calibrate, press the PROG key; both the °C and °F symbols flash.
* Using the
s
and
t
keys, correct the pressure value so that it coincides with the one measured by
the reference instrument.
* Press the PROG key. The instrument quits the calibration process and returns to normal opera-
ting mode.
CONNECTING THE DISSOLVED OXYGEN PROBES
To measure dissolved oxygen in liquids, the instrument DO 9709 uses polarographic measuring
probes with two or three electrodes, with an internal temperature sensor in the measuring cell.
Dissolved Oxygen probe connection diagram.
The dissolved Oxygen probe of the instrument DO 9709 is to be connected to the input A. Such
probe is fitted with a DIN 41524 8-pole male connector.
Attention when taking the temperature measurement.
The dissolved Oxygen probe contains a temperature sensor inside of it, with which to make
the calculations for the thermal compensation of the membrane permeability, the saturation
index, and for measuring the concentration of dissolved Oxygen.
ENGLISH
137
DO 9709
B
A
6
1
4
7
3
5
8
2
Dissolved Oxygen Probe
Dissolved Oxygen Probe
Instrument
+5V
7
OUT V
ANODE
3
GND
6
-5V
8
OUT T
1
OUT O2
4
GND O2
5
Dissolved Oxygen Probe input
7
3
5
6
1
4
8
2
+5V
7
OUT V
ANODE
3
GND
6
-5V
8
OUT T
1
OUT O2
4
GND O2
5
