P 1000, 2000, 3000 & 5000 Ex
Ion Science Ltd
Page 32 of 41
Maintenance
Blowing out the PID Cell will fix 99% of maintenance problems
When using the PID instrument 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. This issue can be resolved by the user in the field using the
following procedure and a can of computer duster air.
First remove the lamp, following the instructions on lamp removal from the
cleaning the lamp section below (steps 1 – 6). Using a can of computer
duster, spray air down the small metal tube. Replace the lamp and cap and
test the instrument.
1.
Keep the PID detector lamp window clean.
2.
Replace the sample filters on a regular basis.
Frequency of cleaning the detector lamp and replacement of the filter depends
on the type of gas being detected and the quality of the background air.
3. Secondary Probe Filter
Designed to strengthen the instrument response, even in condensing
environments.
If the instrument background reading is high, change the main probe filter
first. If the readings remain high it will be necessary to change the secondary
probe filter as follows;
a)
Using an 11mm (7/16”) spanner unscrew the probe fitting from the end
of the PID detector nozzle.
b)
Remove and discard the secondary probe filter.
c)
Insert a new secondary probe filter into the probe fitting.
d)
Screw the probe fitting back onto the nozzle and tighten using the
11mm (7/16”) spanner.
CAUTION: DO NOT OVERTIGHTEN THE PROBE FITTING
Cleaning the P Lamp
The P PID relies on an ultraviolet light source ionising VOC gases as they pass across the lamp
window. This process may result in a very fine layer of contamination appearing on the detector window that
must be removed on a regular basis.
CAUTION!
The P is a sensitive detector. Internal components must be
handled with clean hands and clean tools. The P lamp is fragile.
Handle with great care!
1.
Ensure that the P is switched OFF.
2.
Remove the probe and filter
.
Unscrew the black knurled ring to
expose the detector lamp.
3.
Push a lamp-removing sleeve over the end of the lamp. This
allows the user to grip the glass.
