Potter PS120 Series User manual

MFG. #5400933 - REV E
09/12
PRINTED IN USA PAGE 1 OF 3
PS120 SERIES
SUPERVISORY PRESSURE SWITCH
Installation
The Potter PS120 Series Supervisory Pressure Actuated Switches are
designed primarily to detect an increase and/or decrease from normal system
pressure in automatic re sprinkler systems. Typical applications are: Wet
pipe systems with excess pressure, pressure tanks, air supplies, and water
supplies. The PS120 switch is factory set for 120 PSI (8,3 BAR) normal
system pressure. The switch marked with the word LOW is set to operate at
a pressure decrease of 10 PSI (0,7 BAR) at 110 PSI (7,6 BAR). The switch
marked with the word HIGH is set to operate at a pressure increase of 10
PSI (0,7 BAR) at 130 PSI (9 BAR). See section heading Adjustments and
Testing if other than factory set point is required.
1. Connect the PS120 to the system side of any shutoff or check valve.
2. Apply Teon tape to the threaded male connection on the device.
(Do not use pipe dope)
3. Device should be mounted in the upright position.
(Threaded connection down)
4. Tighten the device using a wrench on the ats on the device.
Wiring Instructions
1. Remove the tamper resistant screw with the special key provided.
2. Carefully place a screwdriver on the edge of the knockout and sharply
apply a force sufcient to dislodge the knockout plug. See Fig. 9
3. Run wires through an approved conduit connector and afx the
connector to the device. A NEMA-4 rated conduit tting is required
for outdoor use.
Potter Electric Signal Company • St. Louis, MO • Customer Service: 866-572-3005 • Tech Support: 866-956-0988 • Canada 888-882-1833 •www.pottersignal.com
Service Use:
Automatic Sprinkler NFPA-13
One or two family dwelling NFPA-13D
Residential Occupancy up to four stories NFPA-13R
National Fire Alarm Code NFPA-72
UL, cUL, and CSFM Listed, FM and LPC Approved, NYMEA
Accepted, CE Marked
Dimensions: 3.78" (9.6cm)W x 3.20" (8.1cm)D x 4.22" (10.7cm)H
Enclosure: Cover- Die-cast with textured red powdercoat nish, single
cover screw and rain lip.
Base- Die-cast
Pressure Connection: Nylon 1/2" NPT male
Cover incorporates tamper resistant fastener that requires a
special key for removal. One key is supplied with each device.
For optional cover tamper switch kit, order Stock No. 0090200.
See bulletin #5401200 PSCTSK.
Switch Contacts: SPDT (Form C)
10.1 Amps at 125/250VAC, 2.0 Amps at 30VDC
One SPDT in PS120-1, Two SPDT in PS120-2
Environmental Specications:
NEMA 4/IP66 Rated Enclosure - indoor or outdoor when used
with NEMA 4 conduit ttings.
Temperature range: -40°F to 140°F (-40°C to 60°C)
Pressure Range: 25-175 PSI (1,7 - 12,1 BAR)
Differential: Typical 2 lbs. at 25 PSI (0,14 at 1,7 BAR)
8 lbs at 175 PSI (55 at 12,1 BAR)
Maximum System Pressure: 300 PSI (20,68 BAR)
Factory Adjustment: PS120-1 operates on decrease at 110 PSI (7,6 BAR)
PS120-2 operates in increase at 130 PSI (9 BAR) and
on decrease at 110 PSI (7,6 BAR)
Conduit Entrance: Two knockouts provided for 1/2" conduit. Individual
switch compartments and ground screw suitable for
dissimilar voltages
Tamper:
4. Connect the wires to the appropriate terminal connections for the
service intended. See Figures 2,4,5,6, and 8. See Fig. 7 for two switch
one conduit wiring.
Adjustment And Testing
The operation of the pressure supervisory switch should be tested upon
completion of installation and periodically thereafter in accordance with
the applicable NFPA codes and standards and/or the authority having
jurisdiction (manufacturer recommends quarterly or more frequently).
Note: Testing the PS120 may activate other system connected devices.
The use of a Potter BVL (see product bulletin 8900067 for details) is
recommended to facilitate setting and testing of the PS120 pressure switch.
When a BVL (bleeder valve) is used, the pressure to the switch can be
isolated and bled from the exhaust port on the BVL without effecting the
supervisory pressure of the entire system. See Fig. 3
The operation point of the PS120 Pressure Switch can be adjusted to any
point between 25 and 175 PSI (1,7 - 12,1 BAR) by turning the adjustment
knob(s) clockwise to raise the actuation point and counter clockwise to
lower the actuation point. In the case of the PS120-2, both switches operate
independent of each other. Each switch may be independently adjusted to
actuate at any point acrosss the switch adjustment range. Initial adjustment
can be made with a visual reference from the top of the adjustment knob
across to the printed scale on the switch bracket. Final adjustments should
be veried with a pressure gauge.
Ordering Information
Model Description Stock No.
PS120-1 Pressure switch with one set 1341203
SPDT contacts
PS120-2 Pressure switch with two sets 1341204
SPDT contacts
Hex Key 5250062
Cover Tamper Switch Kit 0090200
BVL Bleeder valve 1000018

MFG. #5400933 - REV E
09/12
PRINTED IN USA PAGE 2 OF 3
PS120 SERIES
SUPERVISORY PRESSURE SWITCH
Typical Sprinkler Applications
Switch Clamping Plate TerminalDimensions
OUTGOING INCOMING
DWG# 923-3
Fig. 1 Fig. 2
Fig. 3
PS120
SUPERVISORY
PRESSURE
SWITCH
BLEEDER
TEST
VA LVE
BVL
WET SYSTEM
ALARM CHECK
VA LVE
PS10
WATERFLOW
ALARM
SWITCH
WATER
MOTOR
GONG
RBVS
RBVS
CHECK
VA LVE
EXCESS
PRESSURE
PUMP OS & Y
VA LVE
WATER
BY-PASS
TEST VA LVE
RBVS
DWG #926-1A
Typical Connections
Fig. 4
An uninsulated section of a single conductor
should not be looped around the terminal and
serve as two separate connections. The wire
must be severed, thereby providing supervision
of the connection in the event that the wire
becomes dislodged from under the terminal.
NOTE: To prevent leakage, apply Teflon tape sealant to male threads only.
2.87
[72.97]
4.22
[107.19]
2.48
[62.87]
3.78
[95.89]
3.20
[81.28]
1.60
[40.64]
GROUND
SCREWS
DWG# 930-1
1/2" NPT
ADJUSTMENT
KNOB
COM1 2
EOLR
TO FIRE
ALARM
PA NEL
TO FIRE
ALARM
PA NEL
EOLR
COM
12
2
1
COM
HIGH
AIR
LOW
AIR
PS120-1 PS120-2
WITH NORMAL SYSTEM
PRESSURE APPLIED LOW -
TERMINAL 2 CLOSES ON
PRESSURE DROP.
WITH NORMAL SYSTEM
PRESSURE APPLIED
HIGH - TERMINAL
1 WILL CLOSE ON
PRESSURE INCREASE.
DWG# 933-1
Closing of any shutoff valves between the alarm check valve and the
PS10 will render the PS10 inoperative. To comply with IBC, IFC,
and NFPA-13, any such valve shall be electrically supervised with a
supervisory switch such as Potter Model RBVS.

MFG. #5400933 - REV E
09/12
PRINTED IN USA PAGE 3 OF 3
PS120 SERIES
SUPERVISORY PRESSURE SWITCH
DWG# 928-4
Break out thin section of divider to provide path for wires
when wiring both switches from one conduit entrance.
One Conduit Wiring
Fig. 6
Fig. 8
DWG#928-5
Fig. 9
Removing Knockouts
C
C
C12
C12
LOW PRESSURE SWITCH
HIGH PRESSURE SWITCH
DWG# 930-3
Changing Pressure
Low Pressure Signal Connection
EOLR
TO FIRE ALARM PANEL
DWG# 928-1
EOLR
TO FIRE ALARM PANEL
DWG# 928-2
High Pressure Signal Connection
Fig. 5 Fig. 7
(With normal system pressure)
Engineer/Architect Specications Pressure Type Waterow Switch
Pressure type supervisory switches; shall be a Model PS120 as
manufactured by Potter Electric Signal Company, St. Louis, MO., and shall
be installed on the re sprinkler system as shown and or specied herein.
Switches shall be provided with a ½" NPT male pressure connection to be
connected into the air supply line on the system side of any shut-off valve.
A Model BVL bleeder valve as supplied by Potter Electric Signal Company
of St. Louis, MO., or equivalent shall be connected in line with the PS120 to
provide a means of testing the operation of the supervisory switch. (See Fig. 3)
The switch unit shall contain SPDT (Form C) switch(es). One switch shall
be set to operate at a pressure decrease of 10 PSI (0,7 BAR) from normal.
If two switches are provided, the second switch shall be set to operate at a
pressure increase of 10 PSI (0,7 BAR) from normal.
Switch contact shall be rated at 10.1Amps at 125/250VAC and 2.0Amps
at 30VDC. The units shall have a maximum pressure rating of 300 PSI
(20,68 BAR) and shall be adjustable from 25 to 175 PSI (1,7 to 12,1 BAR).
• Installation must be performed by qualied personnel and in accordance with all national and
local codes and ordinances.
• Shock hazard. Disconnect power source before servicing. Serious injury or death could result.
• Read all instructions carefully and understand them before starting installation. Save
instructions for future use. Failure to read and understand instructions could result in improper
operation of device resulting in serious injury or death.
• Risk of explosion. Not for use is hazardous locations. Serious injury or death could result.
• Do not tighten by grasping the switch enclosure. Use wrenching ats on the
bushing only. Failure to install properly could damage the switch and cause
improper operation resulting in damage to equipment and property.
• To seal threads, apply Teon tape to male threads only. Using joint compounds
or cement can obstruct the pressure port inlet and result in improper device
operation and damage to equipment.
• Do not over tighten the device, standard piping practices apply.
• Do not apply any lubricant to any component of the pressure switch.
Terminal #1: Closed under
normal system pressure.
Terminal #2: Open under
normal system pressure,
closes on pressure drop. Use
for low pressure signal.
Terminal #1: Open under
normal system pressure, closes
on pressure increase. Use for
high pressure signal.
Terminal #2: Closed under
normal system pressure.