ESAB ET 220i AC/DC, Руководство по эксплуатации

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ET 220I AC/DC
Manual 0-5346 INSTALLATION, OPERATION AND SETUP
3-3
3.07 Electromagnetic Compatibility
WARNING
Extra precautions for Electromagnetic
Compatibility may be required when this
Welding Power Source is used in a domes-
tic situation.
A. Installation and Use - Users Responsibility
The user is responsible for installing and using the welding
equipment according to the manufacturer’s instructions. If
electromagnetic disturbances are detected then it shall be
the responsibility of the user of the welding equipment to
resolve the situation with the technical assistance of the
manufacturer. In some cases this remedial action may be
as simple as earthing the welding circuit, see NOTE below.
In other cases it could involve constructing an electromag-
netic screen enclosing the Welding Power Source and the
work, 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 or may not be
earthed for safety reasons. Changing the
earthing arrangements should only be
authorised by a person who is competent to
assess whether the changes will increase
the risk of injury, e.g. by allowing parallel
welding current return paths which may
damage the earth circuits of other equip-
ment. Further guidance is given in IEC
60974-13 Arc Welding Equipment - Installa-
tion and use (under preparation).
B. Assessment of Area
Before installing 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 tele-
phone cables; above, below and adjacent to the welding
equipment.
2. Radio and television transmitters and receivers.
3. Computer and other control equipment.
4. Safety critical equipment, e.g. guarding of industrial
equipment.
5. The health of people around, e.g. the use of pacemakers
and hearing aids.
6. Equipment used for calibration and measurement.
7. The time of day that welding or other activities are to be
carried out.
8. The immunity of other equipment in the environment:
the user shall ensure that other equipment being used
in the environment is compatible: this may require ad-
ditional protection measures.
The size of the surrounding area to be considered will
depend on the structure of the building and other activities
that are taking place. The surrounding area may extend
beyond the boundaries of the premises.
C. Methods of Reducing Electromagnetic Emissions
1. Mains Supply
Welding equipment should be connected to the mains
supply according to the manufacturer’s recommenda-
tions. If interference occurs, it may be necessary to take
additional precautions such as filtering of the mains
supply. Consideration should be given to shielding the
supply cable of permanently installed welding equip-
ment in metallic conduit or equivalent. Shielding should
be electrically continuous throughout 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 Welding Equipment
The 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 welding equipment is in
operation. The welding equipment should not be modi-
fied in any way except for those changes and adjust-
ments covered in the manufacturer’s instructions. In
particular, the spark gaps of arc striking and stabilising
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. Equipotential Bonding
Bonding of all metallic components in the welding in-
stallation and adjacent to it should be considered. How-
ever. Metallic components bonded to the work piece will
increase the risk that the operator could receive a shock
by touching the metallic components and the electrode
at the same time. The operator should be insulated from
all such bonded metallic components.
5. Grounding of the Workpiece
Where the workpiece is not bonded to earth for electri-
cal safety, nor connected to earth groundbecause of it’s
size and position, e.g. ship’s hull or building steelwork,
a connection bonding the workpiece to earth ground
may reduce emissions in some, but not all instances.
Care should be taken to prevent the grounding of the
workpiece increasing the risk of injury to users, or dam-
age to other electrical equipment. Where necessary, the
connection of the workpiece to earth should be made
by 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.
6. Screening and Shielding
Selective screening and shielding of other cables
and equipment in the surrounding area may alleviate
problems of interference. Screening the entire welding
installation may be considered for special applications.