Varian 450-GC, User Manual

Page: 161 / 205

Detectors – Pulsed Flame Photometric Detector (PFPD) Detectors – Pulsed Flame Photometric Detector (PFPD)
Page: Page: 366 366 User User Manual Manual 450-GC 450-GC Varian, Varian, Inc. Inc.
7. 7. Adjust Adjust the the Air2 Air2 mass flow controller valve until flow rate is near 10 mL/min. mass flow controller valve until flow rate is near 10 mL/min.
Write down and save the dial Write down and save the dial setting for the setting for the Air2 Air2 mass flow controller valve. mass flow controller valve.
Turn the Turn the Air2 Air2 flow controller Off. flow controller Off.
8. 8. Adjust Adjust the the Hydrogen Hydrogen mass flow controller valve until flow rate is near mass flow controller valve until flow rate is near
12 mL/min. 12 mL/min.
If you will If you will be using hydrogen as your carrier gas, the tota be using hydrogen as your carrier gas, the total hydrogen flow l hydrogen flow
to the detector should be approximately 12 mL/minute. The flow rate set to the detector should be approximately 12 mL/minute. The flow rate set
in this s
in this s tep should thus be 12 tep should thus be 12 mL/min minus th mL/min minus th e a e anticip nticip ate ated column fl d column fl ow ow
rate rate. Write down and save the dial setting . Write down and save the dial setting for t for t he Hydrogen ma he Hydrogen mass f ss f low low
controll controll er valve. er valve.
9. 9. Restore Restore the the Air1 Air1 and and Air2 Air2 flow controllers to flow controllers to the settings recorded above. the settings recorded above.
Restore the carrier gas flow to Restore the carrier gas flow to the column. Remove the flow measurement the column. Remove the flow measurement
adapter, remove any Teflon thread tape residue from the igniter cap. adapter, remove any Teflon thread tape residue from the igniter cap.
Lea Leave the flow controll ve the flow controll ers ON ers ON at a at all ti ll ti mes unless you must mes unless you must turn them off turn them off
to re-plumb or reconfigure the gas chromatogra to re-plumb or reconfigure the gas chromatograph. If you turn t ph. If you turn t he flow he flow
controll controll ers off f ers off f or an extende or an extended period then on d period then on aga again, they must in, they must
equilibrate overnight before the PFPD can achieve optimum equilibrate overnight before the PFPD can achieve optimum
performance.
performance.
10. Turn the PFPD and thereby the igniter ON. 10. Turn the PFPD and thereby the igniter ON.
Calibrating the Flow Controllers Calibrating the Flow Controllers
For best stability of For best stability of flows, flow flows, flow controll controll ers should have pre ers should have pressure applied ssure applied
to them for at least 24 hours before adjustments are made. A moderate to them for at least 24 hours before adjustments are made. A moderate
flow of gas through the flow controller during this conditioning period is
flow of gas through the flow controller during this conditioning period is
also helpful in stabilizing the flow contro
also helpful in stabilizing the flow contro ller. ller.
Tools and equipment needed to complete the following procedure. Tools and equipment needed to complete the following procedure. Refer to Refer to
parts and supplies parts and supplies ,, on page 412 on page 412 ..
••
Varian Varian Intelligent Intelligent Digital Digital Flowmeter Flowmeter or or Soap flowmeter. Soap flowmeter.
••
Stopwatch. Stopwatch.
••
Flow Flow measuring measuring adapter adapter (1/8"-to-1/16" (1/8"-to-1/16" Swagelok® Swagelok® reducing reducing union). union).
••
1/4" 1/4" flat flat blade blade screwdriver. screwdriver.
1. 1. Turn off th Turn off the column e column flow. Or, if yo flow. Or, if you want flow u want flow to continu to continue to the e to the column, column,
disconnect the column from the detector and use a column nut and 1/16" disconnect the column from the detector and use a column nut and 1/16"
no-hole ferrule to seal the detector.
no-hole ferrule to seal the detector.
2. 2. Write down Write down the current the current dial setting dial settings for Air1, Air2 s for Air1, Air2 and Hydrog and Hydrogen, then en, then turn turn
off each flow controller. off each flow controller.
3. 3. Install the Install the flow measu flow measuring ad ring adapter (1/8 apter (1/8" to 1 " to 1/16" redu /16" reducing un cing union). Use ion). Use
Teflon thread tape to make a gas-tight seal. Teflon thread tape to make a gas-tight seal.