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complete with associated input filters. In all cases electromagnetic disturbances shall be
reduced to the point, where they are no longer troublesome.
NOTE: The welding circuit may not be earthed for safety reasons. Changing the
earthling arrangements should only be authorized by a person who is competent to
assess whether the changes will increase the risk of injury.
2.
Assessment of area
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, signaling 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 immunity of other equipment in the environment is compatible. The user shall
ensure that other equipment being used in the environment is compatible. This may
require additional protection measures;
8) The time of day that welding or other activities are to be carried out.
3. Methods of reducing emissions
1) Public supply system
Arc welding equipment should be connected to the public supply system according to the
manufacturer’s recommendations. If interference occurs, it may be necessary to take
additional precautions such as filtering of the public supply system. Consideration should
be given to shielding the supply cable of permanently installed arc welding equipment, in
metallic conduit or equivalent. Shielding should be electrically continuous its length. The
shielding should be connected to the welding power source so that good electrical contact
is maintained between the conduit and the welding power source enclosure.
2) Maintenance of the arc welding equipment
The arc welding equipment should be routinely maintained according to the
manufacturer’s recommendations. All access and service doors and covers should be
closed and properly fastened when the arc welding equipment is in operation. The arc
welding equipment should not be modified in any way, except for those changes and
adjustments covered in the manufacturer’s instructions. In particular, the spark gaps of arc
striking and stabilizing devices should be adjusted and maintained according to the
manufacturer’s recommendations.
3) Welding cables
The welding cables should be kept as short as possible and should be positioned close
together, running at or close to the floor level.
4) Equipotent bonding
Bonding of all metallic components in the welding installation and adjacent to it should
be considered. However, metallic components bonded to the word piece will increase the
risk that the operator could receive an electric shock by touching these metallic
