Installation Guide
28
PRESSURE SWITCHES
CONSTRUCTION & OPERATION
Vent Port
Sensing PortFlexible Diaphragm
Wiring TerminalsSwitch Contacts
Normal State
(open switch contacts)
Activated State
(closed switch contacts)
Internal Linkage
Normal State Activated State
Blower Prover
Pressure Switch
Normally open contacts ,
close on a rise in pressure .
Blocked Exhaust
Pressure Switch
Normally closed contacts,
open on a rise in pressure
.
Blocked Intake Air
Pressure Switch
Normally closed contacts,
open on a fall in pressure .
CONSTRUCTION
TYPES AND APPLICATION