Hypertherm POWERMAX1250 Operator's Manual page 5

ELECTROMAGNETIC COMPATIBILITY (EMC)
instructions. In particular, the spark gaps of arc
striking and stabilizing devices should be adjusted
and maintained according to the manufacturer's
recommendations.
Cutting cables
The cutting cables should be kept as short as
possible and should be positioned close together,
running at or close to the floor level.
Equipotential bonding
Bonding of all metallic components in the cutting
installation and adjacent to it should be
considered. However, metallic components
bonded to the workpiece will increase the risk that
the operator could receive a shock by touching
these metallic components and the electrode at
the same time. The operator should be insulated
from all such bonded metallic components.
Earthing of workpiece
Where the workpiece is not bonded to earth for
electrical safety, nor connected to earth because
of its size and position, for example, ship's hull or
building steelwork, a connection bonding the
workpiece to earth may reduce emissions in
some, but not all instances. Care should be
taken to prevent the earthing of the workpiece
increasing the risk of injury to users, or damage to
other electrical equipment. Where necessary, the
connection of the workpiece to earth should be
made by a direct connection to the workpiece, but
in some countries where direct connection is not
permitted, the bonding should be achieved by
suitable capacitances selected according to
national regulations.
ii
8-06
Note: the cutting circuit may or may not be
earthed for safety reasons. Changing the earthing
arrangements should only be authorized by a
person who is competent to assess whether the
changes will increase the risk of injury, for
example, by allowing parallel cutting current return
paths which may damage the earth circuits of
other equipment. Further guidance is given in
IEC/ TS 62081 Arc Welding Equipment Installation
and Use.
Screening and shielding
Selective screening and shielding of other cables
and equipment in the surrounding area may
alleviate problems of interference. Screening of
the entire plasma cutting installation may be con-
sidered for special applications.
Hypertherm
Plasma Systems