OSCO JH-DC, Installation Manual

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5
JH-DC OPERATOR INSTALLATION GUIDE
The limit nuts are not preset at the factory and must be adjusted for the height of the door the operator is installed on. The limit switches
are activated by two threaded nylon rotary limit nuts which are attached to a threaded shaft and driven by chain and sprockets. Remove
the cardboard filler before attempting to adjust the limit nuts.
With the door connected to the door operator in a mid-travel position, and the power disconnect switch turned OFF , disconnect the
operator by using the manual disconnect lever. Instructions for the manual disconnect can be found in the individual operator owner’s
guides. Once the operator has been disconnected, manually move the door by hand to within a foot of its fully open position.
Once the door is in this position, adjust the open limit nut until it activates the limit switch for open, LSO-1 . Press down on the detent plate
and rotate the nut along the threaded shaft.
Once the open limit nut is set, repeat the above process for the close direction nut, (and LSC-1 limit switch).
After finishing the initial limit nut adjustments, reposition the door to approximately its center of travel. Re-engage the operator and turn
the power disconnect
ON. Stand clear of any moving parts and press the OPEN button on the three-button station. If door begins to close
instead of open, stop the door. Locate the motor board in the operator control box with terminals M1 and M2 (motor leads) on it. Swap
these two wires to reverse rotation. Observe the door as it runs through a complete cycle in both directions, and adjust your limits again
if necessary. Fine levels of adjustment can also be achieved by adjusting a few teeth on the nut at a time. If the door stops in midtravel,
the open or close current sensor adjustment or the maximum run timer may need adjustment (see page
13 ).
LIMIT NUT ADJUSTMENTS
OSCO has also supplied two auxiliary limit switches that can be used to control a variety of
devices. Consult the operator wiring diagram for additional details.
The switches are rated 250VAC, 3 amps maximum.
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