Explosion Proof
Alarm Pressure Switch
System Sensor’s EPSEXP series is designed to handle
extreme conditions.
• Designed and approved to operate in hazardous locations
• Rugged NEMA 4 rated cast aluminum housing
• Field-adjustable pressure sensitivity
• ½˝ NPT male brass fitting
These units are ideal for installation in hazardous locations classified
as follows:
Class I, Groups B, C, D, Division 1 & 2
Class II, Groups E, F, G, Division 1 & 2
Class III, Division 1 & 2
Robust Construction. The EPSEXP series consists of a rugged,
NEMA 4 rated cast aluminum housing. Designed for both indoor and
outdoor use, the EPSEXP series operates across a wide temperature
range, from –40°F to 160°F.
• Synchronized activation circuit
• Two conduit entrances
• Tamper resistant screw
• SPDT (Form C) synchronized switches enclosed in a durable
terminal block
Reliable Performance. The EPSEXP series cover is secured with a
tamper resistant screw to prevent unauthorized tampering. Inside,
two sets of SPDT (Form C) synchronized switches are enclosed in a
durable terminal block to assure reliable performance.
Simplified Operation. Like all System Sensor pressure switches,
the EPSEXP series is designed for easy installation. The EPSEXP series
includes a pressure adjustment wheel that requires no special tools.
This feature permits field-adjusting of the activation switch.
Agency Listings
EPSEXP Specifications
Architectural/Engineering Specifications
Model shall be EPS10EXP or EPS40EXP or EPS120EXP pressure type waterflow switch as manufactured by System Sensor of St. Charles, IL. They shall be installed
on the sprinkler system with connection as shown on the drawings and/or as specified herein. Pressure switches shall be of the bellows activated type. Switches
shall have a maximum service rating of 250 psi and shall be factory adjusted to operate at a pressure as follows: EPS10EXP: 4 to 8 psi, EPS40EXP: 10 to 100 psi,
EPS120EXP: 10 to 200 psi. There shall be two (2) contacts rated at 10.0 A @ 125/250 VAC and 2.5 A @ 6/12/24 VDC. The contractor shall furnish and install, where
indicated on the plans, pressure switches according to appropriate NFPA standards. Switches shall be provided with ½˝ NPT male connection to be connected
into the air supply line on the system side of any shut-off valve. Switches shall provide one (1) knockout type and one (1) open hole for ½˝ conduit fitting
attachment and a ground screw provision for electrical grounding. The switch enclosure shall be weatherproof and carry a NEMA 4 rating when used with
proper electrical fittings and conduit. The cover shall incorporate a tamper-resistant screw. Switches shall be listed by Underwriters Laboratories. It shall be rated
for use in hazardous locations classified as Class I, Division 1, Groups B, C, D; Class II, Division 1, Groups E, F, G; Class III, Division 1.
Standard Specifications
Hazardous Locations
Class I, Div 1, Groups B, C, D
Class II, Div 1, Groups E, F, G
Class III, Div 1
Maximum System Pressure
250 psi (max.)
Pressure Connection
½˝ NPT male brass fitting
Contact Ratings
Two sets of SPDT (Form C)
10.0 A, ½ hp @ 125/250 VAC
2.5 A @ 6/12/24 VDC
Overall Dimensions Installed
4.9˝ W × 9.5˝ H
Conduit Entrances
Two openings for ½˝ conduit
Operating Temperature Range
–40°F to 160°F (–40°C to 71°C)
Enclosure Rating
NEMA 4 – suitable for indoor/outdoor use
Shipping Weight
6.2 lbs.
Service Use
Automatic Sprinkler: NFPA-13
National Fire Alarm Code: NFPA-72
3 years
Pressure Ratings
Model Number
Maximum Adjustment Factory Setting
Pressure Range
Operates at rising pressure of 4 to 8 psi
4 to 20 psi
Approx. 3 psi throughout range
Operates on increase at 50 psi and on decrease at 30 psi
10 to 100 psi
Approx. 3 psi @ 10 psi, 6 psi @ 100 psi
Operates on increase at 125 psi and on decrease at 105 psi
10 to 200 psi
Approx. 3 psi @ 10 psi, 9 psi @ 200 psi
Ordering Information
Model No.
Pressure Range
4 to 20 psi
10 to 100 psi
10 to 200 psi
Replacement Hardware Kit (contains tamper screws, wrenches, and conduit plug
O-ring for cover
3825 Ohio Avenue • St. Charles, IL 60174
Phone: 800-SENSOR2 • Fax: 630-377-6495
©2007 System Sensor.
Product specifications subject to change without notice. Visit for
current product information, including the latest version of this data sheet.
A05-1031-002 • 3/07 • #1800