Hy-Security HTG 320-2, Installation And Maintenance Manual

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Installation and Maintenance Manual
12
HTG 320 Manual Operation
A bypass valve has been provided that can override the hydraulic lock that normally secures the arm
from being lifted. In the event of a power failure, manual operation is achieved through the following
procedure.
1. Find the manual bypass valve with the black round knob, which is located on the hydraulic pump
just above where the hoses connect. (See drawing HTC35 ST on page 10). Pull and twist the
valve to engage the manual mode. The barrier arm can now be manually lifted, beginning from
the tip, by moving “hand over hand” while walking towards the operator. When the arm is open,
be certain to close the bypass valve to prevent the arm from drifting down.
2. The arm can be manually closed with the same procedure, except that once manually started, the
arm will fully close itself due to the force of gravity.
3. To regulate the speed of closing, during manual operation only, there is a needle valve for flow
adjustment, which is located just above the manual bypass valve (see drawing HTC35 ST on
page 10). If adjustment is necessary, loosen the lock nut and turn the adjuster stem clockwise to
slow the rate of manual closure. The correct adjustment allows the arm to close at a moderate
speed and stop without excessive bouncing at the fully closed position.