Ascension 5442P, Operating Manual

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Operating Manual SECTION 1
PROTEGE 5442P
7 112509 Rev G
Description of Operation
Two hydraulic cylinders raise and lower the platform. When the "Up" circuit is
energized, an electric motor operates a hydraulic pump which provides pressurized
hydraulic fluid to the cylinders, causing the cylinder rods to extend and raise the
platform. When the "Down" circuit is energized, a hydraulic valve is shifted so that the
fluid flows in the opposite direction through the hydraulic circuit and the platform is
lowered.
A gate at each end of the lift permits passengers to enter and leave the platform. The
lower landing gate will open only when the platform is lowered all the way. The upper
landing gate can be fully opened only when the platform is at the upper landing. Both
gates are self-closing.
The height limit sensor is located in the left-hand machinery cabinet. This switch halts
the movement of the platform when it reaches the upper landing, and its adjustment
must be confirmed every time the lift is relocated.
The motion of the platform is controlled by any of the three operating switches located
on the right side of the lift. These are constant-pressure type switches, so that when a
switch is released the platform stops. It takes approximately 40 seconds for the
platform to move through its full range of 42 inches. These switches are interlocked so
that while one switch is activated, pressing another switch in the opposite direction will
not cause the lift to stop; the original action will continue.
The lift is equipped with an under-platform safety pan that will halt all motion of the
platform if it encounters an obstruction as it descends. If this occurs, use the hand pump
or setup key to raise the platform and allow for the removal of the obstruction. The
under-platform safety pan completely covers the bottom and side edges of the platform.