
Adjustments To Factory Settings
Both EPS10-1 and EPS10-2 devices are pre-adjusted at the
factory to alarm at 4–8 PSI on rising pressure (see Table
2). Pressure switch settings may be adjusted in the field to
obtain a different pressure alarm response from 4 PSI to 20
PSI. The switch has an override feature on the adjustment
mechanism to prevent exceeding the 20 PSI max. setting of
the switch. This override feature carries with it a tolerance
band that may limit the upper adjustment to 16–20 PSI.
Care must be used when setting the switch to ensure that
the lower limit of 4 PSI is not exceeded. This will allow the
switch to reset within the 3 PSI differential stated.
1. Install pressure switch as stated in “INSTALLATION”
portion of instruction manual. Attach pressure test
source to system.
2. Back off locking screw (see Figure 1) to allow main
adjustment wheel to rotate freely.
3. Test trip point by slowly introducing pressure from the
pressure test source. When trip point is found, reduce
pressure to zero. Rotate main adjustment wheel (coun-
terclockwise to increase pressure) and retest until switch
trip point is at the desired pressure setting (4–20 PSI
range). Each number represents an approximate trip
point change of 0.2 PSI. One full rotation changes the
trip point setting by approximately 2.5 PSI. A reset dif-
ferential of approximately 3 PSI is typical throughout the
entire adjustment range of switch.
4. Retest the set point several times to ensure accuracy of
setting.
5. Re-seat locking screw.
Table 2.
Factory Settings (PSI)
MODEL Fall
(Low Switch)
Approx.
Reset
Rise
(High Switch)
EPS10-1
EPS10-2
–– ––
–––– 3 PSI diff.
3 PSI diff.
4– 8
4– 8
Approx.
Reset
D770-08-00 3 I56-0551-007R
NOTE: The sensor assembly is not field replaceable. Do not
attempt to disassemble these parts. If you have any
questions, consult System Sensor. System Sensor
recommends careful consideration of the follow-
ing factors when specifying and installing Alarm
Pressure Switches. Always refer to the Installation
and Maintenance Instruction for specific recom-
mendations on individual devices before installing
the unit.
• Electrical ratings stated in literature and on name-
plates should not be exceeded.
• Overload on switch can cause failure on the first
cycle. Always wire devices according to national and
local electrical codes.
• Install units away from shock and vibration. Proper
electrical fittings should be used to prevent moisture
from entering the enclosure via the conduit.
• Test all devices for proper operation after initial instal-
lation. Perform preventive maintenance and periodic
testing as required by the applicable NFPA standards
but not less than bimonthly.
• Install a back-up control for all critical applications
where control failure could endanger life or property.
A backup control to serve as a high or low limit con-
trol is especially recommended for applications where
a runaway condition could result.
• Do not mount unit where ambient temperatures will
exceed published limits.
• Avoid impact or mechanical loading.