The gas flows through the manually operated shut off valve into the primary regulator. This regulator reduces the high
cylinder pressure to an intermediate pressure. The intermediate pressure gas flows through the pneumatic valve to the
line regulator for its final (line) pressure reduction for use in the health care facility. Two line pressure regulators are
installed in parallel and each is capable of maintaining a constant dynamic delivery pressure at the maximum designed
flow rate of the system. Only one line regulator is in service at any given time and the other is held in reserve. The
reserve regulator can be serviced if necessary.
We recommend that the line regulators alternate actively supplying pressure to the piping system on a monthly basis.
This means that each line regulator will have one month of active service followed by one month of rest.
Pressure relief valves are installed down stream of all pressure regulators and are set at no more than 50% above the
setting of the pressure regulator located immediately upstream. All the pressure relief valves are capable of fully
relieving the pressure at the set point. All pressure relief valves are piped together to allow for the installation of a
single vent line leading outside.
The pneumatic valve is
the key “automatic” mechanism in the 4000 Series Manifold. It is the bank switching control
that assures the uninterrupted flow of gas at an unfluctuating delivery pressure. When the operating bank pressure
falls to a predetermined level, the pneumatic valve automatically switches to the fresh (reserve) cylinder bank.
CAUTION
ALL PRESSURE ADJUSTMENTS SHALL BE MADE BY AUTHORIZED PERSONNEL ONLY.
INCORRECT PRESSURES CAN AFFECT CYLINDER BANK SWITCHING AND RESETTING
WHICH CAN DISRUPT GAS DELIVERY.
The 4000 Series Manifold control cabinet has two means of providing continuous status information on the system.
First, pressure gauges to indicate the bank pressures and the delivery pressure. Second, six (6) indicator LED’s: two
(2) green that indicate cylinder in use, two (2) yellow for Reserve Ready and two (2) red that indicate that a bank is now
depleted.
Bank Change-Over Indicators
The six (6) indicators are controlled by sensing the bank pressure. Replacing the depleted cylinders resets the system,
changing the indicator from red to green. At the same time the yellow LED will change to green when going from
“Reserve” to “in Service”.
Alarm Systems
Allied Healthcare Products, carries a complete line of alarm systems which can be used in conjunction with the 4000
Series Manifold, to provide the required visual and audible signals, when bank switching occurs.
For remote alarm electrical connection, use Electrical Wiring Diagram shown on page 13. The 4000 Manifold System,
when used in conjunction with these alarm systems, complies with CSA Z305.1-M1984. However, since these alarm
systems are external to the manifold, they are not dealt with in detail in this manual
.
Safety Features
Each 4000 Series Manifold is clearly labeled for the only gas it is designed to deliver. A large nameplate is affixed to
the cabinet. The system is gas specific from the Manifold to the cylinder end of the pigtails.
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