11
RECOMMENDATION
TO
REDUCE
ELECTRO-MAGNETIC
EMISSIONS
General
The user is responsible for installing and using the arc welding equipment according to the manufacturer’s
instructions. If electromagnetic disturbances are detected, then it shall be the responsibility of the user of the arc
welding equipment to resolve the situation with the technical assistance of the manufacturer.
Evaluation of the welding area
Before installing arc welding equipment the user shall make an assessment of potential electromagnetic problems in
the surrounding area
a.
Other wiring, control cables, telephones and communication cables; above, below and adjacent to the
welding machine
b.
Radio and television transmitters and receivers;
c.
Computer and other control equipment;
d.
Equipment critical for safety purposes such as safety checks of industrial equipment;
e.
The health of persons in the vicinity, for example persons who wear pacemakers and hearing aids;
f.
Equipment used for calibration or measurements;
g.
The immunity of other equipment in which the equipment is to be used. The user must ensure that other
equipment used in the same place is compatible. This may require additional protection measures;
h.
The time of day when welding or other activities are carried out
i.
The size of the area to be considered will depend on the structure of the building and any other
processes in the area. The surrounding area may extend beyond the boundaries of the buildings.
Recommendation to reduce electro-magnetic emission
a.
Mains power supply
: the equipment must be connected to the power mains as specified in the
Manufacturer’s instructions. If interference occurs, additional precautions such as filtering of the mains
supply may be required. The supply cable in the welding machine’s permanent installations may have to
be screened in metal conduits or similar. The screening should be electrically continuous for the entire
length of the cable. It should also be connected to the welding machine with a good electrical contact
between the metal conduit and the casing.
b.
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.
c.
Protection and reinforcement:
Selective screening and shielding of other cables and equipment in the
surrounding area may alleviate problems of interference. Screening of the entire welding area may be
considered for special applications
d.
Connect the earth directly to the metal piece to be welded
: Where necessary, 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.
