Application Note
Honeywell Pressure Switches
High Pressure: HP Series, HE Series
Medium Pressure: MH Series, ME Series
Low Pressure: LP Series, LE Series
Background
Due to the demanding conditions found within industrial
and transportation industries, pressure switches are often
designed into equipment and vehicle applications to make
or break an electrical connection in response to a system
pressure change. These switches are frequently exposed to
chemical splashes, dirt, grime, and harsh media, as well as
performance spikes. They must provide reliable and consistent
performance and have a high life cycle rating.
Safety and Productivity Solutions
Potential Applications
Transportation
Agricultural
machinery
• Hydraulic and braking systems
• Engine/transmission oil pressure
• Filtration systems
Heavy duty
construction
machinery
• Hydraulic and braking systems
• Engine/transmission oil pressure
• Filtration systems
Heavy duty trucks • Engine/transmission oil pressure
• Filtration systems
Lawn and garden • Engine/transmission oil pressure
• Filtration systems
Marine vessels • Engine/transmission oil pressure
• Filtration systems
Material handling
machinery
• Hydraulic and braking systems
• Engine/transmission oil pressure
• Filtration systems
Railway • Engine/transmission oil pressure
• Filtration systems
Industrial
CNC machines • Cutting fluid
Compressors, boilers • Line pressure
Food and beverage
equipment
• Line pressure
Fracking equipment • Line pressure
Generators • Oil pressure
HVAC/R equipment • Air pressure
Mud pumps • Line pressure
Pneumatic
equipment
• Air pressure
Presses and punches • Hydraulic pressure
Pressure washers • Water pressure
Trash compactors • Hydraulic oil pressure
Water jet cutting
machines
• Water pressure
Water pumps • Lift pressure
Mud pump line pressure measurement
2 sensing.honeywell.com
Application Note
Honeywell Pressure Switches
Solution
Honeywell Pressure Switches are durable, reliable
electromechanical gauge pressure on/off switches that are
available with either single pole single throw (SPST) normally
open or normally closed circuitry, or single pole double throw
(SPDT) circuitry. Their IP67 environmental sealing and high
proof pressure and burst pressure ratings allow for use in many
rugged applications that require the making or breaking of an
electrical connection in response to a pressure change of the
system media.
The media (gas or liquid) pressure is applied via the port of
the switch to a diaphragm or sealed piston. A pre-tensioned
spring on the other side of the sealed piston or diaphragm
controls the set-point pressure. If the force resulting from
the pressure is greater than the tension on the spring, the
electrical contacts within the switch will change state. If the
contacts are normally open when no pressure is applied, they
close on increasing pressure when the set point is reached. On
decreasing pressure, the contacts will open again at a pressure
somewhat less than the set switching point. The difference
between the activation point on increasing pressure and the
deactivation point on decreasing pressure is called hysteresis.
The set point pressure for the switch can be configured such
that the switch will actuate on increasing or decreasing system
pressure.
Features
• Pressure switching set point range: 3.5 psi to 4000 psi
(varies by Series)
• Proof pressure: 500 psi to 10,000 psi (varies by Series)
• Burst pressure: 1250 psi to 20,000 psi (varies by Series)
• Life cycle rating up to 2 million
• IP67 sealing rating (HP, HE, ME, MH, LP, LE Series)
• Operating temperature range 40 °C to 120 °C
[40 °F to 248 °F]
• Hysteresis option (HP, HE, LP Series)
• Variety of pressure ports and electrical terminations
• Switching point accuracy up to ±2 %
• Through optional smart diagnostic technology, Honeywell
pressure switches are able to detect failures such as
open circuits, cut wires, worn insulation, and more (only
available on HP, HE, ME, LP, and LE Series pressure
switches).
• Optional smart diagnostic technology allows up to four
segregated signal amplitudes to perform diagnostics and
status (only available on HP, HE, ME, LP, and LE Series
pressure switches).
Hydraulic and braking systems