Sensus 121 Series - Page 4

4
Atmospheric Regulator or Zero Governor
Size Outlet Pressure Range Springs
3/4", 1" and 1-1/4" 121-8 1-1/2" w.c. vacuum (–1-1/2" w.c.) to + 1-1/2" w.c.
Main Spring (Red-Black) 143-82-021-00
Counterspring (Black-Red) 121-10-021-50
1-1/2", 2" and 2-1/2" 121-12 1" w.c. vacuum (-1" w.c.) to + 1-1/2" w.c.
Main Spring (Red-Black) 143-82-021-00
Counterspring 120-10-021-10
3" and 4" 121-16 1-1/4" w.c. vacuum (-1-1/4" w.c.) to + 1-1/4" w.c. Main Spring only 121-62-021-54
Outlet Pressure Ranges and Springs
Maximum Nominal
Outlet Spring Spring Inlet Diaphragm
Size Pressure Range Color Part Number Pressure Size
1-1/2" to 3-1/2" w.c.
Blue-Black 143-82-021-01 (main spring)
Black-Red 121-10-021-50 (counterspring)
1-1/2" to 12" w.c.
Green-Black 143-82-021-02 (main spring)
Black-Red 121-10-021-50 (counterspring)
3/4", 1" and 1-1/4" ** 3-1/2" to 6-1/2" w.c. Red-Black 143-82-021-00
60 psi 8"
Model 121-8 5" to 8-1/2" w.c. Blue-Black 143-82-021-01
6" to 14" w.c. Green-Black 143-82-021-02
12" to 28" w.c. Green (2" O.D.) 143-16-021-05
1 psi to 2 psi Orange (2" O.D.) 143-16-021-06
2 psi to 4-1/4 psi Black 143-16-021-07
3/4", 1" and 1-1/4" **
3 psi to 6-1/2 psi Cadmium* 143-16-021-08
Model 121-8HP
6 psi to 10 psi
Cadmium* 143-16-021-08 (outer) 60 psi 8"
White 143-16-021-13 (inner)
1-1/2" to 3-1/2" w.c.
Red 143-16-021-03 (main spring)
_
120-10-021-10 (counterspring)
1-1/2" to 12" w.c.
Maroon 121-42-021-00 (main spring)
_
120-10-021-10 (counterspring)
1-1/2", 2" and 2-1/2" 3-1/2" to 6-1/2" w.c. Red (2" O.D.) 143-16-021-03
60 psi 12"
Model 121-12 5" to 8-1/2" w.c. Blue (2" O.D.) 143-16-021-04
6" to 14" w.c. Green (2" O.D.) 143-16-021-05
12" to 28" w.c. Orange (2" O.D.) 143-16-021-06
1 psi to 2 psi Black 143-16-021-07
1-1/2 psi to 3 psi Cadmium 143-16-021-08
1-1/2", 2" and 2-1/2" 1 psi to 2 psi Orange (2" O.D.) 143-16-021-06
60 psi 8"
Model 121-8 2 psi to 4-1/4 psi Black 143-16-021-07
1-1/2", 2" and 2-1/2"
3 psi to 6-1/2 psi Cadmium* 143-16-021-08
Model 121-8HP
6 psi to 10 psi
Cadmium* 143-16-021-08 (outer) 60 psi 8"
White 143-16-021-13 (inner)
3-1/2" to 6-1/2" w.c. Red (3" O.D.) 121-62-021-50
3" and 4"
5" to 8-1/2" w.c. Blue (3" O.D.) 121-62-021-51
15 psi (4" 121)
Model 121-16
6" to 14" w.c. Green (3" O.D.) 121-62-021-52
40 psi (3" 121
16"
14" to 28" w.c. Orange (3" O.D.) 121-62-021-53
1/2 psi to 1-1/4 psi Yellow 121-62-021-56
3" and 4" 1 psi to 2 psi Black 143-16-021-07 15 psi (4" 121
)
12"
Model 121-12 1-1/2 psi to 3 psi Cadmium 143-16-021-08
40 psi (3" 121
*Requires High Pressure Spring Adjustment.
** 3/4" x 3/4" not available.
Installation and Maintenance
Model 121 Regulators