Miller Electric Welding - Manual (Page 28)

OM-169 510 Page 24
SECTION 6 – HF IN PLASMA ARC WELDING
mod6.2* 5/94
WARNING
HIGH-FREQUENCY RADIATION can interfere with radio navigation, safety services, computers,
and communications equipment.
•
Have only qualified person familiar with electronic equipment perform this installation.
•
The user is responsible for having a qualified electrician promptly correct any interference problem resulting from the
installation.
•
If notified by the FCC about interference, stop using the equipment at once.
•
Have the installation regularly checked and maintained.
•
Keep high-frequency source doors and panels tightly shut, keep spark gaps at correct setting, and use grounding and
shielding as shown in Figure 6-3 to minimize the possibility of interference.
ЙЙ
ЙЙ
ЙЙ
Ref. S-0753
1 Plasma Arc Torch
2 High-Frequency Voltage
Used inside torch to ionize gap
between electrode and tip to help
start the pilot arc.
3 Electrode
4 Pilot Arc
5 Tip
6 Shield Cup
1
ЙЙЙ
ЙЙЙ
ЙЙЙ
ЙЙЙ
ЙЙЙ
ЙЙЙ
ЙЙЙ
2 High
3
5
4
Plasma Arc Welding (PAW)
ЙЙЙЙЙЙЙЙ
ЙЙЙЙЙЙЙЙ
ЙЙЙЙЙЙЙЙ
ЙЙЙЙЙЙЙЙ
Frequency (HF)
6
Figure 6-1. High Frequency In Plasma Arc Welding (PAW)
50 ft
(15 m)
Welding Zone
S-0754
1 Sources Of Direct
High-Frequency Radiation
High-frequency source (Plasma
Arc Welding power source),
cables, torch, work clamp, work-
piece, and work table.
2 Sources Of Conduction Of
High Frequency
Input power cable, line disconnect
device, and input supply wiring.
3 Sources Of Reradiation Of
High Frequency
Ungrounded metal objects, light-
ing, wiring, water pipe and fixtures,
external phone and power lines.
3
2
2
1
1
3
1
3
3
Figure 6-2. Sources Of High-Frequency Radiation From Incorrect Installation