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machine, the highest voltage, with which it is possible to come into contact,
is the open-circuit voltage between the welding clamps. In our generator
this voltage is 58V.
•
The maximum open-circuit voltage of the welding machines is established
by national and international standards (EN 60974-1) depending on the
type of weld 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 mechanically
with increased protection for
the operator
DC current: 141V
peak value
AC current: 141V
peak value and
100V effective
•
In case 1, the dc welding machines with rectifier must be built in such a
way that, in case of a fault developing in the rectifier (for example open
circuit, short circuit or lack of power), the permitted values cannot be
exceeded. The welding machines of this type can be marked with the
symbol:
S
•
Before opening the machine switch off the machine and disconnect it from
the power socket.
•
Only personnel authorised by this company can carry out maintenance on
the machine.
3
ELECTROMAGNETIC COMPATIBILITY (EMC)
This welding machine conforms to EN 60974-10 standard. However, the
electromagnetic emissions generated could prove not be compatible with the
maximum permitted levels for some classes of electrical equipment, such as
the following:
•
Domestic electronic appliances (radios, TVs, videos, telephones,
burglar alarms, etc.).
•
Computers, robots, electro-medical instruments and life-support
systems.
•
Radio-television transmitters and receivers.
•
Pacemakers and hearing aids.
