attachment 2 section i ? technical specifications commuter coach ...

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ATTACHMENT 2
shall be provided which shall be controlled by the Wabco ECU via the I/O controls multiplex modules
and shall serve as a means of providing the operator with the operating condition of the antilock brake
system. All electrical connections on the antilock system shall be Meritor Wabco molded connectors.
The Wabco ECU shall utilize 4 amp “JUNIOR-POWER-TIMER” series connectors.
The Data Link function shall be provided which enables the Wabco ECU to report its operating
condition to an external source. The controller data link configuration shall conform to SAE standard
J1708 and the coded language used shall conform to SAE J1587. Two connections in the controller
shall be provided.
The Meritor Wabco D-Cab 4S/4M ABS system is an approved equal.
3.5.1.5 AIR SYSTEM
The coach air system shall operate all accessories and the braking system with reserve capacity.
The engine drive air compressor shall be sized to charge the air system from 0 psi. to the governor
cutoff pressure (130 psi.) in less than 3 minutes while not exceeding the engines rated speed. The air
compressor shall be set to cut in at 105 psi.
Regardless of the systems air pressure, idle up to the rated engine speed shall be available to the driver
with the transmission in neutral and the parking brake applied.
With the air system fully charged and the engine shut off, the reservoir capacity shall be sufficient to
permit four full brake applications to maintain 60 psig. The pressure relief valve shall be mounted in
the compressor cylinder head. The muffler or ping tank shall be mounted in the engine compartment
relative to the air compressor discharge port. A drain mounted on the muffler or ping tank shall be
directed or piped so as to discharge below the engine cradle or bulkhead level.
Air lines, except necessary flexible lines, shall conform to the installation and material requirements of
SAE Standard J844-Type 1 or ASTM B-75 for copper tubing with standard, brass, flared or ball sleeve
fittings, or SAE Standard J844-Type 3B for nylon tubing or ASTM
D-1248, Type 1, Class C Grade E5 for polyethylene tubing if not subject to temperatures over 200 0 F.
Accessory and other noncritical lines may use Type 3A tubing. Nylon tubing shall be installed in
accordance with the following color coding standards:
Green Indicates primary brakes and supply
Red Indicates secondary brakes
Brown Indicates parking brake
Yellow Indicates compressor governor signal
Black Indicates accessories
Blue Indicates suspension
Line supports shall prevent movement, flexing, tension strain, and vibration. Copper lines shall be
supported by looms, grommets, or insulated clamps to prevent the lines from touching one another or
any component of the coach. To the extent practicable and before installation, the lines shall be prebent
on a fixture that prevents tube flattening or excessive local strain. Copper lines shall be bent only