It has been brought to the attention
of the Association ofWelding
Distribution’s (AWD) Product
Safety & Quality (PSQ) Committee
that some welding and cutting
equipment suppliers are offering
inverter plasma cutters that use a
torch connection system, which may
leave exposed connections at very
high voltage levels.

The picture shows the male torch
connector exposed while the torch
switch is still in place and able to
activate the machine’s output. This
may expose the operator or persons
in the vicinity to direct contact with
voltage levels which may cause death
by electrocution. The AWD points to
the following extract from EN 60974
-1:2005 copyright IEC:2005:
“11.1.4 Rated no-load voltage for
special processes for example plasma
cutting. A rated no load voltage
exceeding 113V peak DC may only be
used if the following requirements
are fulfilled: These power sources
with their corresponding torches
shall prevent the output of no-load
voltage if the torch is disassembled
or disconnected from the power
source.”
The AWD PSQ committee advises
that it is normal for plasma cutters to
have a no-load voltage exceeding
200VDC.Most manufacturers use a
torch connected within the housing
of the machine or a connector which
disables output if the torch is
removed.