Thermal Dynamics CUTMASTER 81, Руководство по обслуживанию

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Manual 0-2957 4-19 TROUBLESHOOTING
F. Output Power Tests
1. No DC Output
1. Activate the torch.
• If INV ON indicator D13 on Logic PC Board
does not turn ON, then replace the Logic PCB.
• If the INV ON indicator D13 blinks ON then
OFF immediately, perform the following test:
2. Turn input power OFF, and bleed down the system.
3. Attach a #12 wire jumper between the work lead
and terminal E35 or E62 on the Output Power PC
Board on the right side of the power supply.
4. Remove the tip and electrode from the torch.
WARNING
The following tests must be performed with the power
supply connected to primary input power. There
are extremely dangerous voltage and power levels
present inside this unit. Do not attempt to diagnose
or repair without proper training in power electron-
ics measurement and troubleshooting techniques.
The next step will defeat the safety interlock feature.
Proceed with caution.
5. Turn on primary input power and the gas supply.
Activate the torch switch. Gas should flow, then
stop after 2 seconds. Front panel DC indicator
should turn on.
6. Measure open circuit voltage between E61(+) to
E43 (-) at the Output Power PC Board. Voltage
should be greater than 200 V. If voltage is
less
than 10 V, refer to the diode test measurements
in Section 4.10-C.
2. Gate Drive & Sensing
1. Shut off input power. Replace the torch tip and
electrode. Remove the jumper betweenthe work lead
and terminal E35 or E62 on the Output Power PC
Board.
2. Install a jumper between TP1 and TP7 on the Logic
Board. Refer to Logic Board layout.
3. When the unit is turned on, the DC light should
remain ON.
4. Activate the torch. After two seconds INV ON Indi-
cator (D13) on the Logic PCB should come on and
remain on.
• If INV ON indicator does not remain on, replace
Logic PCB.
• If INV ON indicator remains on, then check for
at least 2 vdc between TP-1 to TP-11 and be-
tween TP-1 to TP-10 on the Logic PCB. Refer to
Logic Board Layout.
• If no voltage, replace Logic PC Board.
• If voltage is correct, measure for at least 2
vdc between points as in the following chart:
E11 J3 E11 J2B
E19 J10A E19 J10B
IGBT A IGBT B
• If voltage is 0, replace Main PCB.
This completes the test procedures.