DESCRIPTION/APPLICATION
RANCO commercial pressure controls are used for either
operating or protecting commercial refrigeration or air
conditioning systems. They are suitable for R12, R22, and R502
refrigerants and are available with either male flare or capillary flare
nut connections. Both low pressure (suction sensing) and high
pressure (discharge sensing) versions are available.
These controls, with NEMA 1 enclosures and snap action switches,
may be used in a variety of applications: direct control of motors
or compressors; with a contactor for pilot duty control; to control
solenoid valves. The electrical ratings inside the control cover must
not be exceeded.
O10 Single pole, single throw (SPST)
close (cut-in) on rise
open (cut-out) on drop
O11 Single pole, single throw (SPST)
open (cut-out) on rise
close (cut-in) on drop
O16 Single pole, double throw (SPDT)
2-3 close on rise, open on drop
2-1 close on drop, open on rise
O20 Double pole, single throw (DPST)
close (cut-in) on rise
open (cut-out) on drop
3
2
1
L
L
T
T
DIFFERENTIAL
ADJUSTMENT
SCREW
CW increases
CCW decreases
See p. 3
RANGE
ADJUSTMENT
SCREW
CW lowers
CCW raises
See p. 3
COVER
SCREW
All O series are available in the automatic reset/cycling version.
Manual reset versions of the O16 are available.
NO!
NO!
DIFF
HIGH EVENT
3
12”
0
10
20
30
40
50
0
1
2
3
35
25
15
5
2
1
PSI. bar
CLOSES ON PRESSURE RISE.
SWITCH LOW EVENT
IS HIGH EVENT
MINUS DIFF
bar PSI.
DIFF
HIGH EVENT
3
12”
0
10
20
30
40
50
0
1
2
3
35
25
15
5
2
1
PSI. bar
CLOSES ON PRESSURE RISE.
SWITCH LOW EVENT
IS HIGH EVENT
MINUS DIFF
bar PSI.
DIFF
HIGH EVENT
3
12”
0
10
20
30
40
50
0
1
2
3
35
25
15
5
2
1
PSI. bar
CLOSES ON PRESSURE RISE.
SWITCH LOW EVENT
IS HIGH EVENT
MINUS DIFF
bar PSI.
YES!
IMPORTANT NOTICE
MANUAL OPERATION (tripping switch)
The switch can be manually operated by lifting
the bellows to tabs as shown. Operating the
control at any other point WILL CAUSE
CONTROL DAMAGE AND VOID THE
WARRANTY.
DO NOT REMOVE the protective switch cover.
INSTALLATION
CAUTION:
To prevent possible electrical shock or equipment damage,
disconnect electrical power to unit before and during installation.
DO NOT restore electrical power to unit until the control is properly
installed and grounded. DO NOT locate the control in an explosive
atmosphere as a safety hazard can result due to possible spark
generation in the control.
Controls are not to be located in areas of extreme moisture,
dirt or dust, or in a corrosive or explosive atmosphere. These envi-
ronments can shorten control life.
1
INSTALLATION DATA
O10/011/O16/O20
SINGLE PRESSURE CONTROL
