Sharp SH-920 Instruction Manual page 59

Electronic-related defects, Causes and Remedy
【II】
General (machines without CE)
A.
No. Defects
A- Rapid and auto
1 cross-feed are
not functioning.
A- Automatic cross
2 feed does not
reverse and runs
to one direction
Causes
1) SA31 doesn't switch on to
the right side.
2) SA3 and SA31 switches
are defective or wires loose.
3) MCU (motor control unit) is
not working.
Or fuse of MCU is defective.
(no power is delivered
because fuse is broken).
4) Limit Switch LS1 or LS2 for
max stroke safety control is
defective or being pressed.
5) PL-4P (PNP) Proximity
switch is too loose to engage
directional cam or LS5 is not
working.
6) The clamping plates for
saddle are not taken off.
1) Limit Switch LS3 and LS4
are not working or the trip
dog is too loose to control
LS3 and LS4.
P.59 OF 70
Remedy
Please switch it to the right
position.
Fix wires well or replace
new switch.
Check the terminal block as
following:
1. Short 75 and 76 by a wire.
2. Turn SA3 to either the
right side or the left one
and stay in that position.
(not let it turn back)
3. Check whether the
voltage of 73 and 74 is
around 220V±10% or not ;
if not, it indicates that the
MCU is out of order.
Check LS1 and LS2
throughout or replace with
new switches.
Fix it well or replace a new
one.
Please take off the clamping
plates.
Fix trip dog or change to a
new limit switch.