Vagrant Welding Currents; Emc Measures - Fronius LaserHybrid Ultracompact Twin Operating Instructions Manual

Vagrant welding
currents

EMC measures

If the following instructions are ignored, vagrant welding currents may occur.
These can destroy earthed conductor terminals, the power source being
used, the LaserHybrid welding head and other electrical equipment.
Ensure the workpiece clamp is connected tightly to the workpiece.
On electrically conductive floors, the power source must be set up in such a
way as to be insulated from the floor, wherever possible.
Warning, electromagnetic field. Electromagnetic fields may cause as yet
unknown damage to health.
It is the operator's responsibility to ensure that no electromagnetic interference
occurs in electrical and electronic devices.
If electromagnetic interference is found to be occurring, the owner/operator is
obliged to take all necessary measures to prevent this interference.
Check for possible problems, and check and evaluate neighbouring devices'
resistance to interference according to national and international require-
ments:
- Safety devices
- Power, signal and data transfer lines
- IT and telecommunications devices
- Measuring and calibrating devices
- The health of persons in the vicinity, e.g. users of pacemakers and hear-
ing aids
Individuals with pacemakers must seek advice from their doctor before ap-
proaching the welding work area.
Supporting measures for avoidance of EMC problems:
a) Mains supply
- If electromagnetic interference arises despite the correct mains con-
nection, additional measures are necessary (e.g. use of a suitable
line filter)
b) Welding power-leads
- must be kept as short as possible
- must be laid close together (also to avoid EMC problems)
- must be laid apart from other leads
c) Equipotential bonding
d) Earthing of the workpiece
- If necessary, establish an earth connection using suitable capacitors.
e) Shielding, if necessary
- Shield off other nearby devices
- Shield off entire welding installation
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