37
Part No. 6-847703-00 Rev. C00
Operation
Manifold Switch-Over
After electrical power has been applied to
manifold and both banks pressurized, manifold will
automatically select left bank of liquid containers
as primary bank. Right bank of high-pressure
cylinders is designated as secondary bank. Left
bank green “IN USE” light and right bank yellow
”READY” light is illuminated.
Solenoid valve directs dome bias pressure to
bank regulator on left side. If we use a 55 PSI
oxygen manifold as an example, output of left
bank pressure regulator is approximately 125 PSI
(70 PSI base pr 55 PSI bias pressure).
Output of right bank regulator is 70 PSI (base
pressure only, no bias pressure). Since left bank
regulator has highest pressure, all flow is supplied
by left bank of liquid containers.
After left side liquid containers have been
depleted, pressure falls to left secondary supply
pressure switch setting (100 PSI). Left side
pressure switch opens signaling circuit board to
energize solenoid valve. Solenoid valve vents
dome bias pressure from left bank regulator and
directs bias pressure to right bank regulator.
Green “IN USE” light on left side turns off and red
"EMPTY" light illuminates. Yellow “READY” light
on right side turns off and green "IN USE" light
illuminates. A set of normally-closed dry switch
contacts, available inside power supply, opens in
order to signal master alarm panel
(“SECONDARY SUPPLY”).
Since right bank regulator has dome bias
pressure applied, its output pressure is boosted to
approximately 125 PSI. Left bank regulator has
no dome bias pressure and its output pressure is
controlled only by base pressure (70 PSI). All flow
is supplied by right bank of high-pressure
cylinders.
When liquid containers on left side are
replaced, and pressure is restored, manifold will
automatically switch back to left bank. Solenoid
valve will deenergize and direct dome bias back to
left dome regulator.
Right bank green “IN USE” light will turn off and
yellow "READY" light will illuminate. Left bank red
“EMPTY” light will turn off and green “IN USE”
light will illuminate. Switch contacts inside power
supply will close in order to cancel master alarm
panel signal (SECONDARY SUPPLY).
As a rule, when liquid containers are attached
to left bank and adequate pressure is applied
(pressure switch closed), manifold will always
default to left bank. If right bank high-pressure
cylinders falls below approximately 500 PSI, right
bank red “EMPTY” light will illuminate and
secondary supply alarm contacts will open.
In event of a power failure, unpowered solenoid
valve will direct dome bias pressure to left bank
regulator. A secondary supply alarm will be
activated on master alarm panel. All flow will be
supplied by left bank of liquid containers until
depleted. Right bank of high-pressure cylinders
will then automatically begin to supply flow.
If a situation occurs where both banks are
depleted, intermediate pressure will begin to drop
from 125 PSI to “RESERVE IN USE” pressure
switch setting of 80 PSI. At 80 PSI, normally-
closed switch will open and red “RESERVE IN
USE” light on front of power supply will illuminate.
A set of normally-closed dry switch contacts,
available inside power supply, will open in order to
signal master alarm panel. Intermediate pressure
will continue to drop until reaching reserve header
regulator setting of 70 PSI. At this point, all flow
will be supplied by high pressure cylinders
connected to reserve header assembly.
When pressure in reserve header high-
pressure cylinders drop to 1500 PSI, reserve low
normally-closed pressure switch will open. A set
of normally-closed dry switch contacts, available
inside power supply, will open in order to signal
master alarm panel.
