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MULTIWELD 250T-C / 320T-C / FV 220M-C EN
All welders should take the following precautions in order to minimise exposure to the electromagnetic elds (EMF) generated by the
welding circuit::
• position the welding cables together – if possible, attach them;
• keep your head and torso as far as possible from the welding circuit;
• never enroll the cables around your body;
• never position your body between the welding cables. Hold both welding cables on the same side of your body;
• connect the earth clamp as close as possible to the area being welded;
• do not work too close to, do not lean and do not sit on the welding machine
• do not weld when you’re carrying the welding machine or its wire feeder.
People wearing pacemakers are advised to consult their doctor before using this device.
Exposure to electromagnetic elds while welding may have other health eects which are not yet known.
RECOMMANDATIONS TO ASSES THE AREA AND WELDING INSTALLATION
Overview
The user is responsible for installing and using the arc welding equipment in accordance with the manufacturer’s instructions. If
electromagnetic disturbances are detected, it is the responsibility of the user of the arc welding equipment to resolve the situation
with the manufacturer’s technical assistance. In some cases, this remedial action may be as simple as earthing the welding circuit.
In other cases, it may be necessary to construct an electromagnetic shield around the welding power source and around the entire
piece by tting input lters. In all cases, electromagnetic interferences must be reduced until they are no longer bothersome.
Welding area assessment
Before installing the machine, the user must evaluate the possible electromagnetic problems that may arise in the area where the
installation is planned.
In particular, it should consider the following:
a) the presence of other power cables (power supply cables, telephone cables, command cable, etc...)above, below and on the sides
of the arc welding machine.
b) television transmitters and receivers ;
c) computers and other hardware;
d) critical safety equipment such as industrial machine protections;
e) the health and safety of the people in the area such as people with pacemakers or hearing aids;
f) calibration and measuring equipment
g) the isolation of the equipment from other machinery.
The user will have to make sure that the devices and equipments that are in the same room are compatible with each other. This
may require extra precautions;
h) make sure of the exact hour when the welding and/or other operations will take place.
The surface of the area to be considered around the device depends on the the building’s structure and other activities that take place
there. The area taken in consideration can be larger than the limits determined by the companies.
Welding area assessment
Besides the welding area, the assessment of the arc welding systems intallation itself can be used to identify and resolve cases
of disturbances. The assessment of emissions must include in situ measurements as specied in Article 10 of CISPR 11. In situ
measurements can also be used to conrm the eectiveness of mitigation measures.
RECOMMENDATION ON METHODS OF ELECTROMAGNETIC EMISSIONS REDUCTION
a. National power grid : The arc welding machine must be connected to the national power grid in accordance with the manufacturer’s
recommendation. If interferences occur, it may be necessary to take additional preventive measures such as the ltering of the power
suplly network. Consideration should be given to shielding the power supply cable in a metal conduit. It is necessary to ensure the
shielding’s electrical continuity along the cable’s entire length. The shielding should be connected to the welding current’s source to
ensure good electrical contact between the conduct and the casing of the welding current source.
b. Maintenance of the arc welding equipment : The arc welding machine should be be submitted to a routine maintenance
check according to the manufacturer’s recommendations. All accesses, service doors and covers should be closed and properly locked
when the arc welding equipment is on. The arc welding equipment must not be modied in any way, except for the changes and
settings outlined in the manufacturer’s instructions. The spark gap of the arc start and arc stabilization devices must be adjusted and
maintained according to the manufacturer’s recommendations.
c. Welding cables : Cables must be as short as possible, close to each other and close to the ground, if not on the ground.
d. Electrical bonding : consideration shoud be given to bonding all metal objects in the surrounding area. However, metal objects
connected to the workpiece increase the risk of electric shock if the operator touches both these metal elements and the electrode.
It is necessary to insulate the operator from such metal objects.
e. Earthing of the welded part : When the part is not earthed - due to electrical safety reasons or because of its size and its
location (which is the case with ship hulls or metallic building structures), the earthing of the part can, in some cases but not
systematically, reduce emissions It is preferable to avoid the earthing of parts that could increase the risk of injury to the users or