Honeywell HON 380 User And Maintenance Instructions page 14

Functional diagram of
the HON 380 gas
pressure regulator
How the HON 380 gas
pressure regulator
works
HON 380 gas pressure regulator with HON 673/674 controller
Figure
 The comparator diaphragm of the regulator unit captures the actual value of
the outlet pressure and compares it with the reference variable specified by
the pilot spring.
 A regulation deviation directly influences the closing member posi-
tion via the valve spindle. The flow rate change this causes results in
an adjustment of the outlet pressure actual value so that it matches
the setpoint. When there is zero pressure flow, the device seals
tightly.
 If the actual value of the outlet pressure in the regulating line exceeds or falls
below a certain response pressure, the closing member of the safety shut-off
valve located on the input side shuts off the flow of gas.
 The SAV measuring diaphragm with the switching sleeve moves into
the corresponding disengaged position, the ball engagement
mechanism enables the SAV valve spindle and the control element
of the safety shut-off closes.
 The SAV can only be engaged in the open position manually when the outlet
pressure at the sensing point is at least within the specified re-engage differ-
ential range for overpressure or underpressure relative to the response pres-
sure setpoint.
 The SAV can also be equipped with a manual or a remote release feature, as
desired. It is also possible for it to be executed in functional class A (with dia-
phragm rupture protection) or B (without diaphragm rupture protection).
Description
Color Meaning
Outlet pres-
sure
Atmo-
spheric
pressure
Inlet pres-
sure
14