Service And Maintenance; Maintenance Intervals; Replacing The Drägersensor - Dräger Polytron SE Ex PR NPT1 DD Instructions For Use Manual

Service and Maintenance

Maintenance Intervals

NOTICE
Observe standard EN 60079-29-2 and/or the relevant
national laws and regulations:
Daily
Visual inspection to establish readiness for opera-
tion.
Before operation:
Setting the sensor current, page 36.
Calibrating / adjusting the sensing head, page 37.
At regular intervals,
as specified by those responsible for the gas detection
system and which should not exceed an interval of
6 months:
Check signal transmission to control unit, and alarm
triggering, see instructions for use of the appropriate
central controller.
Calibrating / adjusting the Sensing head, page 37.
The interval for regular calibration depends on the
environmental conditions of use.
Especially it must regularly be ensured that gas can
freely enter the sensor and that there are neither corro-
sion nor deposits of dust, oil or aerosols.
Every six months
Arrange for inspection by trained personnel.
The inspection intervals in each individual case are in-
fluenced and if necessary shortened by technical safety
considerations, engineering processes and the techni-
cal requirements of the equipment.
We recommend a DrägerService contract which also
covers repairs.
If necessary
Replace sensor, page 39.
Replacing the DrägerSensor
It is not allowed to replace the DrägerSensor while it is
energized in the hazardous area.
Furthermore also in the safe area the controller has to
be switched-off before replacing the DrägerSensor.
Otherwise the DrägerSensor might be destroyed dur-
ing the connection procedure.
NOTICE
Observe national regulations for installing electrical
devices in hazardous areas (in Europe EN 60 079-14).
Switch off the controller or remove the corresponding
channel module.
Sensing Heads Polytron SE Ex PR M1/2 DD and
SE Ex LC M1/2 DD
1 2 3
1
2
3
After having switched-off the voltage open the termi-
nal box of the sensing head and remove the upper
section.
1 Disconnect the sensor leads from the terminals.
2 Unscrew hexagon nut.
3 Remove old sensor. Shorten sensor leads of the
new sensor adequately and cut-off the isolation by
approx. 8 to 10 mm. Use ferrules enclosed.
4 Screw in new sensor and secure the hexagon nut
against self-loosening e.g. with Loctite No. 221.
To maintain the ingress protection IP 66 and for rea-
sons of explosion protection observe that the sensor's
O-ring is tightly fitted.
5 Connect sensor leads to terminals:
Terminal 1 – brown lead
Terminal 2 – yellow lead
Terminal 3 – black lead
Close the terminal box ensuring it is dust free.
WARNiNG
1 2 3
1
2
3
WARNiNG
39