Thermal Dynamics DRAG-GUN 38, Инструкция по эксплуатации

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SECTION 5: SERVICE 34 Manual 0-2729
A. Checking Center Insulator
1. Remove the shield cup, tip, gas distributor, and elec-
trode from the torch.
2. Disconnect the torch leads from the power supply to
isolate the torch from power supply circuits.
3. Using an ohmmeter (set to 10K or higher), check for
continuity between the positive and negative torch
fittings. (Red Pilot Return wire and Gas Fitting).
If there is continuity between the two torch fittings
proceed to Step 4.
4. Remove the torch head from the leads (refer to Sec-
tion 5.13, Servicing Torch Head Components).
5. With the torch head disconnected from the leads,
measure the resistance between negative cathode
body of the torch head (where the electrode seats)
and the positive anode body of the torch head (the
outer threads where the shield cup seats).
Infinite resistance (no continuity) should be mea-
sured between negative and positive sections of
the torch head.
If any current can flow through the center insula-
tor, the torch head is faulty and must be replaced.
If the torch head is okay, the problem is in the leads
assembly. Proceed to Step 6.
6. Repeat measurement of step 3 above.
If continuity is found, replace the torch leads.
If no continuity is found, the torch leads are okay
and the problem was in the way the components
were assembled. Proceed to Step 7.
7. Carefully reassemble the components and recheck
the completed assembly per Step 3 to confirm that
the components have been properly assembled.
This completes the checks for the proper operation of the
center insulator of the torch head and leads.
B. Checking Torch Switch
1. Remove right Side Panel of Power Supply per sub-
section 5.11-D.
2. Disconnect the Torch Switch Wire connector from
the Main PC Board at J3 (black and white wires).
A-02124
Torch Switch Connector
(Black & WhiteWires)
Torch Lead
Pilot Wire
(Red)
Figure 5-13 Torch Switch Connector Location
3. Using an ohmmeter set on the Rx1 scale make the
following check:
a. Measure across the Torch Switch Wiring con-
nector, black to white. The meter should indi-
cate an open when the Torch Switch is not
pressed. When pressed the meter should indi-
cate a short.
NOTE
The Shield Cup must be installed to complete the
circuit through the Parts-In-Place (PIP) contacts.
4. Reinstall the Torch Switch Wiring connector back
onto the Main PC Board connector.
C. Checking Torch Leads
1. Check continuity between red wire on E14 and tip.
2. Remove tip, measure for continuity between the elec-
trode and TB1 on torch block.
If either one is open, replace torch leads.