Troubleshooting
Technical Handbook
019722-101 Rev. 05
63
SC-350/360
9
Troubleshooting
9.1 Display is Blank at Switch On
• Check the mains supply cable and the main fuses.
• Check for short-circuits on the PSU/CPU boards, or between the
cables and the chassis.
• Use a DMM to measure the PSU voltage, see
• The green LED on the PSU board, visible through the vent holes,
indicates if there is +5 V supply.
LED not lit up:
No supply. Exchange the PSU board.
LED lit up:
Supply. Exchange the CPU board.
• The automatic thermal power supply cut-off function has been
activated. The power supply has been overloaded. Turn
Off
the
machine. Leave it to cool off for 2-3 minutes. Restart.
Exchange the PSU if the machine is cold and the display still
goes blank.
9.2 Motor Stops
• Check the mains supply cable.
• Ensure that the motor and its axis can rotate freely.
• The motor has an automatic thermal cut-off function that has
been activated. The motor winding has been overheated (140
o
C/
284
o
F ± 5%).
Turn
Off
the machine and let it cool down for 15 minutes or
more (depending on room temperature) to a temperature below
132
o
C/269
o
F and then restart.
• If the machine is cold but the motor still does not work,
exchange the motor.
• Check triac SCR2 on the PSU board (
). Replace it as required.
