PhoCheck TIGER
Ion Science Ltd
Page 35 of 43
Maintenance (continued)
PID Sensor/Lamp replacement and cleaning
When using your TIGER in conditions of high ambient humidity, the PID may show unexpected
readings appearing to increase. This occurs due to dust or other small particles within the
detector becoming hydrated with humidity. This causes these particles to conduct a signal
between the electrodes. The problem can be resolved by the user in the field using the
procedure below and a can of computer duster air.
In normal use the lamp should be cleaned after every 100 hours of use (based on 30 ppm for
100 hours). Reduce this if TIGER is used in heavily gas contaminated environments. Please
note that some esters, amines and halogenated compounds may accelerate window fouling; in
these cases cleaning may be required after every 20 hours of use. Cleaning frequency will also
depend upon alarm levels set and prevailing environmental conditions.
CAUTION!
The TIGER is a sensitive detector. Internal components must be handled with clean hands and
clean tools. The TIGER lamp is fragile. Handle with great care. Never touch the window and
do not drop!!
To remove the Mini PID sensor for cleaning
or lamp replacement, first ensure that the
TIGER is turned off and that you are in a
clean environment such that the sensor
parts will not be contaminated by dust, oil or
grease. Remove the sensor cover (A5 on
page 37). The centre screw may be turned
with a small coin or a suitable flat bladed
screwdriver.
Ensure that the sensor seal (9), on the inside of the sensor cover is not disturbed.
Carefully lift the Mini PID Sensor (A6) from the
TIGER body, ensuring that the two Inlet/Outlet
Seals (10) remain in place in the TIGER body.
Using the special tool prov
ided, locate its „prongs‟ in
the slots in the side of the Sensor body. Using the
forefinger to restrain the sensor, (the internal parts
are spring-loaded and careless disassembly will
leave you hunting for the spring!) squeeze the tool
to release the lamp housing.
The lamp may now be removed.
To replace the lamp or install a new one, reverse the procedure, ensuring the seals
are all in place. When replacing the sensor cover ensure that the markers are
aligned correctly and that the cover is a snug fit.
The instrument MUST be re-calibrated after fitting a replacement or cleaned lamp.
WARNING!
NEVER REFIT A DAMAGED LAMP!
