Safety instructions
General
099-000120-EW501
26.07.2011
11
CAUTION
EMC Machine Classification
In accordance with IEC 60974-10, welding machines are grouped in two electromagnetic
compatibility classes (see technical data):
Class A machines are not intended for use in residential areas where the power supply comes
from the low-voltage public mains network. When ensuring the electromagnetic compatibility of
class A machines, difficulties can arise in these areas due to interference not only in the supply
lines but also in the form of radiated interference.
Class B machines fulfil the EMC requirements in industrial as well as residential areas,
including residential areas connected to the low-voltage public mains network.
Setting up and operating
When operating arc welding systems, in some cases, electro-magnetic interference can occur
although all of the welding machines comply with the emission limits specified in the standard.
The user is responsible for any interference caused by welding.
In order to evaluate any possible problems with electromagnetic compatibility in the
surrounding area, the user must consider the following: (see also EN 60974-10 Appendix A)
• Mains, control, signal and telecommunication lines
• Radios and televisions
• Computers and other control systems
• Safety
equipment
• The health of neighbouring persons, especially if they have a pacemaker or wear a hearing
aid
• Calibration and measuring equipment
• The immunity to interference of other equipment in the surrounding area
• The time of day at which the welding work must be carried out
Recommendations for reducing interference emission
• Mains connection, e.g. additional mains filter or shielding with a metal tube
• Maintenance of the arc welding equipment
• Welding leads should be as short as possible and run closely together along the ground
• Potential
equalization
• Earthing of the workpiece. In cases where it is not possible to earth the workpiece directly,
it should be connected by means of suitable capacitors.
• Shielding from other equipment in the surrounding area or the entire welding system
