Challenge CMT-130, Service Manual, Page: 51 / 226

FEB 2017
CMT 130 Book Trimmer 2-41 2. Status Indicator RAPs
RAP 2.33 Knife Latch Cylinder
Output 3
A pneumatic latch prevents the knife assembly
from moving down any time the hydraulic motor
is not running. The latch is located on the table
at the rear of the machine, Figure 2-51. A spring
return air cylinder drives latch. The latch is en-
gaged whenever the hydraulic motor is off.
Fault Indicator

Knife assembly drift down over time

Knife latch failed to disen-
gage
is displayed
Initial Actions
Perform GP 6.15 Speed-Control Air Valves.
Check for air leaks and disconnected or pinched
hoses.
Check for loose or broken wire 71 at the power
panel.
Check that the wire connector for valve number
8 is connected properly.
Procedure
1. Using ADJ 4.17 Knife Latch, check that the
proximity switch is properly adjusted.
2. Switch off the hydraulic motor by pressing
the either e-stop button. In the power panel,
manually activate valve number 8 by press-
ing the actuator button on the valve (Figure
2-52). Does the latch disengage?
Y N
Disconnect main power and replace valve
number 8 (PL 5.21 Pneu. Manifold Asm.
59012-1).
3. Electrically activate valve 8 by shorting wire
71 to 74. Does the latch disengage?
Y N
Disconnect main power and replace valve
number 8 (PL 5.21 Pneu. Manifold Asm.
59012-1).
4. Disconnect main power and replace the
main PWB (REP 4.22 Main PWB Replace-
ment).
Figure 2-51. Knife Latch
Figure 2-52. Pneumatic Valve #8