Micromeritics AccuPyc 1330 Quick Reference Manual page 85

AccuPyc 1330
TROUBLESHOOTING AND MAINTENANCE
CHECKING THE CELL AND EXPANSION CHAMBERS FOR LEAKS
To check the cell and expansion chambers for leaks perfonn the following procedure.
NOTE
Thls procedure should be performed In a temperature-stable envi-
ronment after the pycnometer has been warmed up for. at least two
hours. Before performing this procedure, check the chamber cap to
ensure that it is not the source of leaks. It
should be free from
partides, the O-ring should be properly seated, and it should not
contain excessive grease.
1.
Allow the pycnometer to equilibrate thennally in a room having a stable temperature.
2. Press
,--I _--,I
WqMM to enter manual mode.
3. If the system has been open, manually pUlge the system before proceeding as follows:
a. Open the EXPAND valve and close the VENT valve. ('The indicator above the key is tumed
on when the valve is open.)
b. Open the FILL valve and fill the sampie chamber to the desired pressure.
c. Close the FILL valve and open the VENT valve.
Repeat this procedure two or three times.
4. Press
Mtiit%m
to open the fill valve.
5. Fill the sampie chamber to 19.5 psig.
6. Press
I!ditJiti
to elose the fill valve.
7. ObseIVe the pressure display. After an equilibration period (about 20 to 30 seconds), the pres-
sure should not vary more than 0.0005 psig/min.
• If the pressure does not vary more than 0.0005 psig/min, proceed to step 8.
• If the pressure varies more than 0.0005 psig/min., temperature instability or a leak may be
indicated. Vent the system, then repeat steps 4 through 7 several times to verify !hat a
leak is indicated. If a leak is indicated, call a Micromeritics SeIVice Representative.
8. Press
nWänfl
to open the expansion valve and
Inntwl
to open the fill valve.
9. Fill the chambers to 19.5 psig.
10. Press
I min l
to elose the fill valve.
15 Dec 89
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