10
MONOGYS
EN
All welders should take the following precautions in order to minimise exposure to the electromagnetic fields (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 fields while welding may have other health effects 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 fitting input filters. 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 specified in Article 10 of CISPR 11: 2009. In situ measurements can also be used to
confirm the effectiveness 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 filtering 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 modified 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 riskof 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 damage other electrical equipment. If necessary, it is appropriate
that the earthing of the part is done directly, but in some countries that do not allow such a direct connection, it is appropriate that the connection is
made with a capacitor selected according to national regulations
.
f. Protection and plating :
The selective protection and plating of other cables and devices in the area can reduce perturbation issues. The
protection of the entire welding area can be considered for specific situations.
