Maintenance; Sensor Replacement - Dräger PEX 3000 Instrucciones Para El Servicio

Maintenance

Maintenance

Sensor Replacement

— Use sensors only which are listed in the order list page 27.
Type XTR 0000, XTR 0001: Ex-Sensor PR M, part-no. 68 09 225,
Type XTR 0010, XTR 0011: Ex-Sensor LC M, part-no. 68 10 350.
Attention:
The transmitter must be de-energised before disconnecting the sensor.
Otherwise then explosion protection is infringed and the sensor might be
impaired during connecting procedure.
Observe national regulations for the installation of electrical apparatus in potenti-
ally explosive atmospheres devices (in Europe EN 60 079-14).
De-energise transmitter or remove the corresponding channel module of the cen-
tral controller.
Loosen four screws on the top of the transmitter's housing and remove the up-
per section.
Disconnect the sensor leads from the terminals. Use screw driver (3 mm width) or
special tool to open the spring terminals. (see page 10 about handling spring ter-
minals).
Unscrew hexagon nut of the old sensor.
Remove old Ex-Sensor out of the housing and replace by a new Ex-sensor. Shor-
ten the sensor leads to 55 mm, strip approx. 6 mm insulation and fix the attached
isolated ferrules (Zoller+Fröhlich, Type: V3AE0003 or equivalent). This ensures
an IP-rating of IP 30 if the transmitter housing is opened for maintenance purpo-
ses.
Screw in new sensor through the corresponding and secure with locking
sealant, e.g. Loctite No. 221. To maintain the IP-rating observe that the sensor's
O-ring is tightly fitted.
Connect the sensor's leads (brown, yellow, black) to the corresponding spring
terminals marked br/br, ge/yw und sw/bk. Use screw driver (3 mm width) or spe-
cial tool to open the spring terminals. (see page X about handling spring termi-
nals).
Observe the atmosphere is free of dust and re-install the upper section of the
housing by means of the four screws.
Energise transmitter again and re-install the corresponding channel module of the
central controller.
Observe warm-up time of the new sensor of about 10 minutes.
Attention:
After replacement of the Ex-sensor the transmitter must be calibrated (see
transmitter calibration, page 17).
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9023810 - 2nd edition - September 2005