Gate Power-Operator Design. A manufacturer's design (using
similar components), the standard features provided, and optional accessories
available are what primarily separates one manufacturer's products from
Some manufacturers provide a full line of power-operators for gates
in all horsepowers, voltages, and phases, while others limit selection to one
or two models which may provide inadequate horsepower and improper voltages
for the gate being designed. Gate power-operator capabilities are of
particular concern when cantilever gates are installed, particularly when the
grade increases from side to side of the opening.
Sliding Gate Power-Operators. Power-operators for sliding gates
can generally be associated in three groups based upon their method of
operation. These are:
Electromechanical Chain Driven - An electric motor drives a
series of reduction and worm gears, chains, and sprockets which in turn drive
a chain attached to the gate thereby operating the gate.
Electromechanical Rack and Pinion - An electric motor,
through gear reduction, operates a rack and pinion gear arrangement attached
to the gate thereby operating the gate.
Hydraulic Compression Rail - An electric motor operates a
hydraulic pump which in turn drives two hydraulic motors. The drive wheel
mounted on each motor is compressed and runs on opposing sides of a rail (leg
of angle iron), with the other angle iron leg attached to the gate to operate
The hydraulic compression rail gate power-operator is preferred
for automating sliding gates at restricted areas. An independent life-cycle
cost analysis, conducted by NCEL, indicates that hydraulic compression rail
gate power-operators for horizontal sliding gates offer reasonable acquisition
cost, low operations and support costs, and the lowest risk to the Government.
Swing Gate Power-Operators. Power-operators for swing gates can
generally be placed in two groups based upon their method of operation. These
Hydraulic Piston - A hydraulic piston is attached between
the gate leaf and an offset post. The piston is extended and contracted to
operate the gate.
Electromechanical Swing Arm - An electric motor, through
gear reduction, operates a primary arm that travels in an arc parallel to the
ground. A second arm is attached between the gate leaf and the primary arm
thereby operating the gate.
While an independent life-cycle cost analysis for swing gate
power-operators has not been made, preliminary analysis indicates that the