QUANTACHROME INSTRUMENTS MVP-6DC - Page 8

8
Substituting into equation (3) P
a
(V
C
– V
S
) and P
1
V
R
for n
a
RT
a
and n
1
RT
a
, respectively, gives
()
(
)
V
P
+
V V
P
=
V
+
V V
P
R
1
SC
a
RSC
2
−
−
(4)
or
()
(
)
(
)
V
P P
=
V V
P P
R
21
SC
a2
−
−
− (5)
Then
V
P P
P P
=
V V
R
a2
21
SC
−
−
− (6)
Since P
a
is made to read zero on the digital meter, that is, all pressure measurements are relative
to P
a
, equation (6) becomes
V
P
P P
=
V V
R
2
21
SC
−
− (7)
or
(
)
[
]
-
P
/
P
V
-
V
=
V
21
RCS
1 (8)
Equation (8) is the working equation employed with the MULTIPYCNOMETER.