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cause noise levels to exceed safe limits. You must protect your ears from
loud noise to prevent permanent loss of hearing.
To protect your hearing from loud noise, wear protective ear plugs and/or
ear muffs. Protect others in the workplace.
Noise levels should be measured to be sure the decibels (sound) do not
exceed safe levels.
The operator must ensure all flammable materials are removed from the
work area to avoid any risk of fire.
The operator must NEVER weld containers that have previously
contained petrol, lubricants, gas or similar flammable materials, even if
the container has been empty for a considerable time. THERE IS A
VERY HIGH RISK OF EXPLOSION.
The operator must be aware of all the special regulations which he needs
to conform to when cutting in enclosed spaces with a high risk of
explosion.
To prevent electric shock, we strongly suggest the following rules:
Do not work in a damp or humid environment.
Do not use the machine if its cables are damaged in any way.
Make sure that the earthing system of the electric equipment is
correctly connected and operational.
The operator must be insulated from the metal components
connected to the return wire.
The earthing of the piece being worked could increase the risk of
injury to the operator.
EN 60974-1 Standard: Open-circuit voltage. During the operation of the
machine, the highest voltage, with which it is possible to come into
contact, is the open-circuit voltage between the clamps.
The maximum open-circuit voltage of the plasma machines is established
by national and international standards (EN 60974-1) depending on the
type of current to be used, on its waveform and on the hazards arising
from the work place. These values are not applicable to the strike
currents and those for stabilisation of the arc that could be above it.
The open-circuit voltage, for as many adjustments as possible, must
never exceed the values relating to the various cases shown in the
following table:
Case Working conditions
Open-circuit voltage
1
Places with increased
risk of electric shock
DC current: 113V
peak value
AC current: 68V
peak value and 48V
effective
2
Places without increased
risk of electric shock
DC current: 113V
peak value
AC current: 113V
peak value and 80V
effective
3
Torches held
DC current: 141V
AC current: 141V
