3
Maximum Inlet
Pressure, psig
Fixed Factor billing
1
1
⁄
4
”
30
o
15
15
15
-
-
-
-
-
-
1
1
⁄
4
”, 243-12
1
1
⁄
2
”, 243-12
2”, 243-12
1
1
⁄
4
”, 243-8
1
1
⁄
2
”, 243-8
2”, 243-8
1
1
⁄
4
”, 243-8HP
1
1
⁄
2
”, 243-8HP
2”, 243-8HP
*1
1
⁄
4
”
10
o
25
25
25
-
-
-
-
-
-
1”
30
o
25
25
25
-
25
25
-
25
25
1
⁄
2
”
10
o
100
100
100
80
80
80
80
80
80
3
⁄
8
”
10
o
125
125
125
100
100
100
100
100
1
⁄
4
”
10
o
125
125
125
125
125
125
125
125
125
.207”
10
o
-
-
-
125
125
-
-
-
-
*1”
10
o
40
40
40
-
-
-
-
-
-
3
⁄
4
”
30
o
-
-
40
-
-
40
-
-
-
3
⁄
4
”
10
o
60
60
60
40
40
40
40
40
*External Control Regulator Only
Regulator
Model
and Size
Regulator accuracy is essen-
tial to measurement accuracy,
and because the 243 is so
precise, it is ideal for Pres-
sure-Factor Measurement,
Pressure Compensated
Metering, Fixed Factor Billing,
etc.
The table below gives the
pressure accuracies obtain-
able with 243-12 and 243-8
regulators at the capacities in
the tables on pages 8 to 19.
The 243 will hold outlet pres-
sure within the indicated per-
centage limits from set flow
(250 scfh) to the flows given in
the capacity tables. Percent-
ages are all based on
absolute pressure using 14.4
psia as atmospheric.
As an example, referring to
page 10, a 1
1
⁄
2
” Model 243-12-
2 with 1” orifice, 30
o
, valve, 15
psig inlet and 11” w.c. set-
point (green spring) at 2” w.c.
droop has a gas capacity of
9800 scfh. Per the below
table, this regulator at these
conditions will hold outlet
pressure at 11” w.c. =
1
⁄
2
% (2”
w.c.) from 250 to 9800 scfh
(based on absolute pressure).
For higher outlet pressures,
greater capacities, increased
accuracies, and excessive
inlet pressure variations, use
the 243-RPC pilot operated
regulator (see page 7).
Set Point
6” w.c.
7” w.c.
11” w.c.
18” w.c.
1psi
1psi
2psi
3psi
3psi
Droop
1” w.c.
1” w.c.
2” w.c.
3” w.c.
0.3 psi
0.2 psi
0.6 psi
0.3 psi
0.6 psi
Accuracy
+
1
⁄
2
% and -
1
⁄
2
%
+
1
⁄
2
% and -
1
⁄
2
%
+
1
⁄
2
% and -
1
⁄
2
%
+ 1% and -1%
+ 1% and -2%
+ 1% and -1
1
⁄
2
%
+ 1% and -4%
+ 1% and -2%
+ 1% and -3
1
⁄
2
%
