DETECTORS
Photo Ionization Detector - PID
General Operating Procedure
1. Alwaysensure that theblackplastichood is inplaceon the lampprior tooperating thePIDdetector. The
hoodcontains thehighvoltagebandwhich ismaintainedatahighpotential;neverattempt toadjust thePID
highvoltagebandunless themainGCpower is turnedoff.
2. TurnON theGC. TurnON thePID lampcurrent
with theflipswitchon theGC’sfrontcontrolpanel.
3. Set thePID current to70 (=0.70ma)with the
trimpot setpointon the topedgeof theGC’s front
control panel. Use the flat blade screwdriver
providedwithyourGC toadjust the trimpot. The
lampshouldemitaviolet-coloredlightvisibledown
thecenterof the tube.
4. Confirm that the lamp is operating at or near
0.70ma by pressing the PID detector ACTUAL
displaybuttonon thefrontcontrolpanel. Thesensitivityof the lamp increasesproportionally to thecurrent
applied,butoperationathighercurrents reduces lamp life. ThePIDoperatingcurrent range is70-125. A
settingof70shouldprovidetheuserwithsufficientsensitivityandlampdurability. MostPIDapplicationscan
beperformedusingLOWgain.
5. Set thePID temperature to150
o
C.
6. Once thedetectorhas reached temperatureand thesignalappearsstable, samplemaybe introduced.
NOTE:Lampsareaconsumablepartof thePIDdetector. It isrecommended tohaveaspare lampavailable
ifcriticalanalysesarebeingperformedat remotefieldsites. Spareandreplacement10.6eVPID lampsare
availableunderSRIpartnumber8670-1242. TeflonsealsareavailableunderSRIpartnumber8670-1244.
PID -Close-up topview
Theviolet light isvisibleherewhen the lamp ison
Thecapillarycolumnenters thePIDcellfrom inside thecolumnoven through thebulkheadfitting in the
insulatedovenwall. Thecolumnmaybe installedwith the lamp inplace. Insert thecapillarycolumn into the
PIDdetector inletuntil thecolumnstopsat the lampwindow inside thePIDcell, thenpull itbackabout1mm
from the lampwindow. Tighten the1/8”nutwith thegraphiteferruleat thePID inlet tosecure thecolumn in
place. Thecollectorelectrode ispositionedat the factoryandshouldnot touch thecolumnundernormal
circumstances.
