Thermal Dynamics CUTMASTER 60i Service Manual page 56

CUTMASTER 60i
ii. If +15V is present on the ribbon cable replace the Control & Display board.
iii. Unlikely that both pin 5 and pin 6 of the ribbon are open at the same time but to be sure check them
for continuity. If OK and the header for J602 is OK, no bent or broken pins we need to determine if
+15V is getting to the Inverter board.
iv. +15V comes from the Bias Supply at J303-6 (wire #33) and goes to the Inverter board at J603-6. Mea-
sure for +15V relative to common at J603-8 (or the work lead). If +15V is present at J603-8 and not
on the ribbon cable (after confirming the ribbon cable has continuity (iii)) replace the Inverter board.
Otherwise check for harness between J303 and J603 for continuity and check for +15V at J3-3-6. If
+15V is not present replace the Bias board.
g. If D101 is lighted but D135 is not blinking then the microprocessor is not working. Replace the Control
& Display board.
3. Display
As the Control & Display board starts, the display shows a sequence of information, up to 4 digits of seven
segments plus decimal.
a. First are the letters
b. Next is the firmware code revision in 3 digits, first digit represents a major revision, the 2nd a minor revi-
sion and the 3rd should always be zero unless it is experimental code that is being tested before released
for production.
c. Next is a combination of letters and numbers called a checksum that can be used to determine if the code
is corrupted. This changes with each revision of the code. If you call our service dept. you may be asked
for the checksum.
d. Lastly if there are no issues detected during power up the display will show the amperage the unit was
set at previously. If there is a problem it will show the letter E plus 3 digits indicating what the issue is.
If a fault code is displayed go to Fault Code section following this section..
4. Fan
As soon as the Bias Supply starts up the fan should run at low speed, very little fan noise. Fan goes to high
speed when the torch trigger (Start) is pressed.
If the fan is shorted, disconnected or open you should have seen a fault code of E009 in which case replace the
fan. However there are other possible fan problems that do not show a code.
Fan not turning:
a. At the Inverter board with the fan connector, J608, still connected, measure for 24 to 26VDC between
J608-1 (+) and J608-2. If it's there replace the fan.
b. If the voltage is not there measure from J608-1 (+) to the work lead connector (secondary common). If
voltage now present likely cause is the Inverter board.
i. Other possible cause is the fan control signal FAN ON at pin 20 of the ribbon from the Control &
Display board. You can measure for a short on the ribbon cable, after removing both ends, between
pins 20 and 21. If shorted replace the ribbon cable.
5-22
meaning revision.
SERVICE Manual 0-5475