Calibration Menu
To enter the calibration menu press the key
than 3 seconds. The display shows a flashing point on the right bottom indicating
the calibration mode.
ZE – Zero Adjustment
Navigate by means of keys
the menu by pressing the keys (
— The display shows the currently measured gas concentration (negative values are
displayed as long as they are not lower than "–9").
Apply zero gas to the sensor and wait for signal stabilisation (max. 3 minutes.)
q
l
Press keys (
+
) to save the displayed value as an up-dated zero point
q
l
Press keys (
+
) again to terminate this function. The display shows ZE again.
l
Press key
step into sensitivity adjustment
or
q
Press key
to step back into measurement mode.
SP – Span Adjustment
Navigate by means of keys
the menu by pressing the keys (
— The display shows the span gas concentration used during the previous calibra-
tion procedure in % LEL.
— Adjust the concentration of the currently used span gas concentration by means
q
l
of key
or
in steps of 1 % LEL between 20 and 99 % LEL (or in steps of
0.1 % LEL between 2.0 and 9.9 % LEL). Pressing the keys for longer activates a
repeat function.
q
l
Press keys (
+
), apply span gas to the sensor and wait for signal stabilisation
(max. 3 minutes).
q
l
Press keys (
+
) to calculate the necessary internal amplification and save it.
q
l
Press keys (
+
) to display a reference value to characterise the sensitivity of the
sensor (constantly amplified bridge signal).
q
l
Press keys (
+
) to terminate this function. The display shows SP again.
q
Press key
twice to step back into measurement mode.
9023810 - 2nd edition - September 2005
l
for more than one second but less
q
l
or
until the display shows ZE ("ZEro") and enter
q
l
+
). The output signal switches to 3.4 mA.
q
l
or
until the display shows SP ("SPan") and enter
q
l
+
).
Calibration Menu
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