Fronius MTG 250i Instructions De Service page 23

If distribution boards, twin-head mounts, etc., are being used, note the following: The
electrode of the welding torch / electrode holder that is not used is also live. Make sure
that the welding torch / electrode holder that is not used is kept sufficiently insulated.
In the case of automated MIG/MAG applications, ensure that only an insulated wire
electrode is routed from the welding wire drum, large wirefeeder spool or wirespool to the
wirefeeder.
EMC Device Clas- Devices in emission class A:
sifications -
-
Devices in emission class B:
-
EMC device classification as per the rating plate or technical data.
EMC measures In certain cases, even though a device complies with the standard limit values for emissi-
ons, it may affect the application area for which it was designed (e.g. when there is
sensitive equipment at the same location, or if the site where the device is installed is
close to either radio or television receivers).
If this is the case, then the operator is obliged to take appropriate action to rectify the
situation.
Check and evaluate the immunity to interference of nearby devices according to national
and international regulations. Examples of equipment that may be susceptible to interfe-
rence from the device include:
-
-
-
-
Supporting measures for avoidance of EMC problems:
1.
2.
3.
4.
5.
Are only designed for use in industrial settings
Can cause line-bound and radiated interference in other areas
Satisfy the emissions criteria for residential and industrial areas. This is also true for
residential areas in which the energy is supplied from the public low-voltage mains.
Safety devices
Power, signal and data transfer lines
IT and telecommunications devices
Measuring and calibrating devices
Mains supply
- If electromagnetic interference arises despite correct mains connection, additio-
nal measures are necessary (e.g. use a suitable line filter).
Welding power leads
- must be kept as short as possible
- must run close together (to avoid EMF problems)
- must be kept well apart from other leads
Equipotential bonding
Earthing of the workpiece
- If necessary, establish an earth connection using suitable capacitors.
Shielding, if necessary
- Shield off other nearby devices
- Shield off entire welding installation
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