Challenge CHAMPION 305 Instructions And Parts Manual page 49

The Knife Up and Knife Down Proximity switches are mounted to a bracket that is attached to
the Knife Cylinder (Figure 38). With the power off, set the collar between the proximity
switches and then turn on power. Press cut buttons once to turn on the hydraulic motor. The
knife will move to the absolute top of its stroke. Move the collar to the top proximity switch
until LED turns on, then move it an additional 1/4" higher and tighten its setscrew. An
indicator light on the switch body comes on when the switch is actuated (proximity switches
must be within 1/8" (3.2mm) to actuate). Check the Knife Down Proximity switch by going into
the Maintenance screen to Knife Adjust and lock the knife in the down position. Check the
distance between the proximity switch and the actuator.
2. Hydraulic Up Proximity Switch
This switch is mounted on the left, rear leg of the base (Figure 39). An indicator light on the
switch body comes on when the switch is actuated (proximity switches must be within 1/8"
(3.2mm) to actuate). The switch senses the extension of the clamp cylinder at the top of its
stroke. This stops hydraulic power to the clamp and knife. If the switch is not properly set,
the knife and clamp cylinders will be under constant load (indicated by excessive heat and
noise).
To adjust:
a. Loosen the bottom lock nut and turn the top lock nut down to raise the switch.
b. Turn on the machine and press the cut buttons once to start the hydraulic motor.
c. The knife and clamp will move to the extreme up position and a load will remain on the
hydraulics.
d. When the cylinder has stopped moving, pass a metal object in front of the switch to
actuate it and take the load off the hydraulics. Keeping pressure on the switch to hold it
against its mounting bracket, turn the lock nut up to lower the switch until the indicator
light in the switch comes on. Tighten the lower jam nut.
e. Press the cut buttons to cycle the clamp and check clamp position.
3. Clamp Up Proximity Switch
This switch is mounted thru the rear of the arch, (Figure 40). It is tripped by the clamp when
the clamp is in the up position. This switch prevents backgauge movement if the clamp is not
up. On machines equipped with the air table option, it also diverts the air from the table when
the clamp is down to prevent the stock from moving during a cut. This switch is tripped by a
Figure 39
12.0 Adjustments
Hyd. Up
Proximity Switch
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