QUANTACHROME INSTRUMENTS MULTIPYCNOMETER Manual page 20

5.5.6. VRc SMALL CALIBRATION (NO SPHERES, LARGE CELL)
5.5.6.1. PERFORM THE STEPS LISTED IN SECTION 5.5.1 (THE PURGE ROUTINE)
WITH THE LARGE SAMPLE CELL IN THE CELL HOLDER.
5.5.6.2. CLOSE TOGGLE VALVES I AND GAS IN. OPEN VALVE II.
5.5.6.3. TURN THE SELECTOR VALVE ON THE FRONT PANEL TO THE CELL
POSITION AND THEN OPEN THE GAS OUT TOGGLE VALVE.
5.5.6.4. TURN THE ZERO ADJUSTMENT KNOB ON THE FRONT PANEL UNTIL A
0.000 PSIG READING IS DISPLAYED ON THE DIGITAL PANEL METER. CLOSE THE
GAS OUT TOGGLE VALVE.
5.5.6.5. TURN THE SELECTOR VALVE TO THE REFERENCE POSITION AND
CLOSE THE GAS OUT TOGGLE VALVE.
5.5.6.6. OPEN THE GAS IN TOGGLE VALVE AND, WHEN THE DIGITAL PANEL
METER READS 17.0 PSIG, CLOSE THE GAS IN TOGGLE VALVE.
5.5.6.7. VERIFY THAT THE PRESSURE DISPLAYED ON THE DIGITAL PANEL
METER DOES NOT CHANGE DURING A 10-SECOND PERIOD. TAKE THE cP1
PRESSURE READING ON THE DIGITAL PANEL METER AND ENTER THAT
NUMBER ON THE INSTRUMENT CALIBRATION SHEET IN APPENDIX B.3, ITEM
B.3.3., AS cP1.
5.5.6.8. TURN THE SELECTOR VALVE ON THE FRONT PANEL TO THE CELL
POSITION.
5.5.6.9. VERIFY THAT THE NEW PRESSURE DISPLAYED ON THE DIGITAL PANEL
METER DOES NOT CHANGE DURING A 10-SECOND PERIOD. TAKE THE cP2
PRESSURE READING ON THE DIGITAL PANEL METER AND ENTER THAT
NUMBER ON THE INSTRUMENT CALIBRATION SHEET IN APPENDIX B.3, ITEM
B.3.3, AS cP2.
5.5.6.10. CALCULATE THE RATIO cP1 / cP2 = cP AND ENTER THIS VALUE AS cP
ON THE INSTRUMENT CALIBRATION SHEETS IN APPENDIX B.3, ITEM B.3.3.
5.5.6.11. REPEAT THE STEPS IN SECTIONS 5.5.5.2 TO 5.5.5.11 UNTIL FIVE
CONSECUTIVE cP VALUES FALL WITHIN +/-0.005 OF EACH OTHER.
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