JUMO 202610.0, Operating Instructions Manual, Page: 43 / 68

43
10 Calibration
Calibrating
✱
Remove transmitter from the sample liquid.
✱
Clean the transmitter externally with a moist cloth or sponge, then dry it
(particularly the membrane). Likewise, remove any dirt or moisture between
the sensor module and the protective membrane.
✱
Position the transmitter just above the surface of the water and wait for the
transmitter temperature-compensation time (about 20 minutes) to elapse.
Avoid direct sunlight.
✱
After removal of the transmitter from pressurized systems, wait for the
output signal to stabilize.
✱
When the output signal has stabilized , start calibration by pressing the
key. Keep the key pressed down for more than 2 seconds. The output
signal will be set to the value (normally 18 mA) that has been defined as the
service current. The calibration procedure is performed automatically,
takes up to 15 minutes and ends automatically.
Successful
calibration for
the version
without display When the calibration has been completed successfully, the two-wire transmit-
ter for dissolved oxygen goes into the measurement mode (mg/l). At a water
temperature of 20°C, an oxygen content of about 9 mg/l will be displayed. The
output signal for the measurement range (where 0 — 20 mg/l corresponds to
4 — 20 mA) will be approx. 11.2 mA.
Successful
calibration for
the version
with display
✱
Press - the freshly determined sensor slope is accepted and the cali-
bration is completed.
The membrane must not be damaged!
The measurement signal may change during calibration! Control
devices or PLCs operated by the transmitter may react in an
undesirable manner! The output signal will be set to the value
(normally 18 mA) that has been defined as the service current.
The transmitter for dissolved oxygen switches over to saturation
measurement (%) during the calibration procedure.
The LC display (on the standard or maximum version) shows
CALIB.
If the setup program is active at the same time, the measurement
display will change from mg/l to %. At the end of the calibration,
100% will not necessarily be indicated, since the old value for the
slope is active during calibration.
CAL
Pressing will cancel the calibration; the original value for the
sensor slope is retained.
PGM
EXIT