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2.ARC WELDING SAFETY PRECAUTIONS (continued)
To prevent electromagnetic troubles, read the following. Also, if electromagnetic
troubles occur, check the following again.
Before installing arc welding equipment the user shall make an assessment of potential
electromagnetic problems in the surrounding area. The following shall be taken into account:
1.
other supply cables, control cables, signalling and telephone cables, above, below and
adjacent to the arc welding equipment;
2.
radio and television transmitters and receivers;
3.
computer and other control equipment;
4.
safety critical equipment, for example guarding of industrial equipment;
5.
the health of the people around, for example the use of pacemakers and hearing aids;
6.
equipment used for calibration or measurement;
7.
The user shall ensure that other equipment being used in the environment is compatible;
8.
the time of day that welding or other activities are to be carried out;
Methods of reducing EMC:
Public supply system
Add a noise filter to the input cables.
Maintenance of the arc welding equipment
Close and fix all doors and covers of the welding machine.
Welding cables
Do not use an unnecessarily long cable.
Place a base metal cable and a torch side cable as closely as possible.
Equipotential bonding
Bonding of all metallic objects in the surrounding area should be considered.
Earthing of the workpiece
The connection of the workpiece to earth should be made by a direct connection to the
workpiece, but in some countries where direct connection is not permitted, the bonding
should be achieved by suitable capacitance, selected according to national regulations.
Screening and shielding
It is selective screening and shielding of other cables and equipment in the surrounding area.
HF