
Operational Use
9023744 - 3rd edition - October 2005
Operational Use
1
The display indicates the measured gas concentration,
2
when the sliding switch is set to »0« = normal and »1« = cal.
— A reference number for the constantly amplified sensor signal is indicated when
the switch is set to »2« = test.
3
A negative signal (dropped below zero) is indicated by a triangle (
l
).
4
Exceeding the measuring range is indicated by an arrow (
Y
).
●
A current between 4 and 20 mA flows through the signal current loop in
accordance to the gas concentration, i. e.:
Using the dust filter
A dust filter can be used with the Ex-sensor PR M (see Order List, order no.
68 10 537). This simply presses into place in the opening in front of the sensor
sintered metal disc and locks in position. The dust filter has virtually no adverse
effect on sensor response times and its influence on sensor sensitivity is minimal.
However, if using a dust filter, it must always be in place when calibration is carried
out. The dust filter should be replaced before calibration.
Interruptions in Operation
e.g. in the event of repair work
— In the event of interruptions in operation, for example during servicing and inspec-
tion, the system is ready for use again after 10 minutes (Ex-sensor warm-up time)
following renewed switch on.
— If necessary, the unit must be recalibrated.
Current
Significance
< 3.0 mA
Malfunction
4 mA
Zero
20 mA
Full scale value
> 20 mA
Measuring range exceeded
02023
7
4
4_1
.eps
2
3
4 1