Dräger Polytron 3000, Инструкция по эксплуатации

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17
Maintenance
Replacing the sensor
The sensor can be replaced, if necessary, without interrupting the power supply in
the explosion-hazard area.
Use only DrägerSensors which are approved for use with the Dräger Polytron 3000
transmitter.

Open the front cover of the service port with an Allen key by turning anticlockwise
(approx. 60
o
). The maintenance switch and potentiometers for calibration are
now revealed.
1 Set maintenance switch to right-hand position. The 4 to 20 mA output changes
to maintenance mode. In this position, a maintenance signal is relayed to the
analogue output and prevents alarms being triggered.
2 Remove bayonet ring from transmitter; pull out old sensor.
3 Remove sensor from packaging. Ensure that the sensor is of the same type as
that specified on the sticker on the measuring unit.

Remove the short-circuit strap from the sensor (if it is fitted).

There is a coded connector on the back of the sensor. Place the sensor in the
opening with the connector at the back and the Dräger logo at the front.
Before plugging the connector in the socket, ensure that they are identically co-
ded. Incorrect connection can damage the sensor!
2 Secure sensor in transmitter with bayonet ring.

Wait until the measured value drops below the alarm threshold set on the central
unit. Otherwise an alarm will be triggered when the maintenance switch is retur-
ned to the measuring position immediately after the sensor replacement.
1 Set maintenance switch to left-hand position.
The 4 to 20 mA output changes to measuring mode.

Refit the front cover of the service port and lock it in place by turning clockwise
with an Allen key (approx. 60
o
).
When the sensor has warmed up:
— Transmitters set for specific calibration with calibration gas

Calibrate sensor, page 14.
— Transmitters set for use of the manufacturer's calibration setting for the sensor.

Transmitter is ready for use.
Disposal of electrochemical sensors:
— Sensors must be disposed of as special waste.
Note the relevant waste disposal regulations.
Further information can be obtained from the relevant local authority and
from appropriate waste disposal companies.
CAUTION
When the transmitter is installed in Ex areas Class II, Div. 1 & 2, Group E, F, G the
opening of the housing (inclusive sensor replacement) must not be done when
connected to power (power must be turned off or the area has to be declassified)!
Explosion hazard!
CAUTION
Use only a 5 mm Allen key without a ball head.
CAUTION
Do not throw sensors into the fire – explosion hazard.
Do not open sensors forcibly – risk of caustic burns.
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