FHM2 Western Digital Manifold
FHM2 Series Fully Automatic Switchover Manifold
The fully automatic changeover manifold is designed to provide a reliable uninterrupted supply of gas to a hospital or
clinic’s medical gas pipeline system. It is designed to meet NFPA 99 type 1 facility requirements.
The fully automatic changeover manifold is designed to provide a reliable uninterrupted supply of gas to a hospital or
clinic’s medical gas pipeline system. It is designed to meet NFPA 99 type 1 facility requirements.
- 24” flexible stainless steel braided pigtails, except oxygen which include rigid copper pigtails. Vertical crossover and staggered configurations include 36” pigtails for half of the cylinders. All pigtails include a check valve.
- CGA connections with integral check valves at each header station.
- Special header configurations available upon request. (U-shaped, L-shaped, etc.) (Dimensional sketch of installation required).
- Built for expansion by adding header extensions
Manifold Design
The manifold control unit includes the following components and features: green “In Service”, yellow “Ready for Use”,
and red “Bank Depleted” indicator lights”, digital cylinder pressure readouts, digital line pressure readout and gauge,
intermediate pressure gauge, internal dual line regulator assembly, intermediate relief valves, line relief valve, and fully
automatic bank switching. Supply bank consist of a header with 24” and/or 36” stainless steel flexible pigtails with check
valves, except oxygen which include rigid copper pigtails with check valves, individual header check valve outlet
bushings, master shut off valves, and union connections for attachment to the control unit. The control unit shall
automatically switch to the secondary bank when the service bank is depleted. Under normal operating conditions, the
gas shall leave the high pressure cylinders through the pigtails into the header bars. The pigtails shall include check
valves to allow the replacement of depleted cylinders without gas pressure back-flow into the remaining depleted
cylinders on that bank. When the depleted cylinders are replaced with full cylinders, the system will automatically reset
itself in preparation for the next bank change.
The only manual activity required by the FHM2 Series manifold control is the changing of the depleted cylinders.
A separate power supply is furnished with the manifold to convert 120 VAC to 24 VAC output power and includes dry
contacts for connecting the “Reserve in Use” alarm to the facility’s master alarm panel/s. The power supply is housed in
a NEMA 3R, enclosure with electrical requirements of 1.5 amp at 120 VAC, 1Ph, 60 Hz. The power supply is CSA
approved.
The manifold control unit includes the following components and features: green “In Service”, yellow “Ready for Use”,
and red “Bank Depleted” indicator lights”, digital cylinder pressure readouts, digital line pressure readout and gauge,
intermediate pressure gauge, internal dual line regulator assembly, intermediate relief valves, line relief valve, and fully
automatic bank switching. Supply bank consist of a header with 24” and/or 36” stainless steel flexible pigtails with check
valves, except oxygen which include rigid copper pigtails with check valves, individual header check valve outlet
bushings, master shut off valves, and union connections for attachment to the control unit. The control unit shall
automatically switch to the secondary bank when the service bank is depleted. Under normal operating conditions, the
gas shall leave the high pressure cylinders through the pigtails into the header bars. The pigtails shall include check
valves to allow the replacement of depleted cylinders without gas pressure back-flow into the remaining depleted
cylinders on that bank. When the depleted cylinders are replaced with full cylinders, the system will automatically reset
itself in preparation for the next bank change.
The only manual activity required by the FHM2 Series manifold control is the changing of the depleted cylinders.
A separate power supply is furnished with the manifold to convert 120 VAC to 24 VAC output power and includes dry
contacts for connecting the “Reserve in Use” alarm to the facility’s master alarm panel/s. The power supply is housed in
a NEMA 3R, enclosure with electrical requirements of 1.5 amp at 120 VAC, 1Ph, 60 Hz. The power supply is CSA
approved.