CIGWELD WELDSKILL 180, Service Manual, Page: 59 / 80

0-5461 10-1 PRELIMINARY TROUBLESHOOTING-POWER SOURCE
SERVICE MANUAL
180
SECTION 10:
PRELIMINARY TROUBLESHOOTING – POWER SOURCE
If the problem cannot be solved by the basic (external) troubleshooting guide, the Power Source covers will
have to be removed to allow the technician to analyse failures with a few common tools.
WARNING
Turn off power and disconnect mains supply plug from receptacle before working on the unit. Allow two minutes for capacitors to
discharge and check that the DC bus voltage has discharged to less than 5VDC, refer to Section 10.04, after disconnection from mains
supply voltage.
10.01 Test Equipment and Tools
• Digital Multimeter
• DC clip-on ammeter
• Screwdrivers and spanners
• CRO (20 MHz bandwidth) & isolating transformer
10.02 How to Remove Cover
• Remove the four screws holding the cover to the machines base and the upper screws in the control panel.
Art # A-13057
• Remove the three screws that hold the rear panel to the machine, two on the top and two at the bottom of
the rear panel.
• Move the rear panel approx. 10mm away from the machine.
• Slide the cover approx. 10mm towards the rear panel then lift up the cover to clear the front panel. Be careful
when lifting up the cover as an earth is connected between the cover & the main earth stud.
10.03 Visually Inspect
Visually inspect the inside of the Power Source. The levels of current present in these units can cause burning or
arcing of PCB, transformers, switches, or rectifier when a failure occurs. Carefully inspect all components within
these units.
Look in particular for the following:
a) Loose or broken wires or connectors.
b) Burned or scorched parts or wires or evidence of arcing.
c) Any accumulation of metal dust or filings that may have caused shorting or arcing.
If any parts are damaged, they must be replaced. Refer to the Spare Parts section for a complete list of components
used in the Power Source.
Locate the faulty component(s) then replace where necessary.