Hypertherm MAXPRO200, Инструкция по эксплуатации

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MAXPRO200
Instruction Manual 807700 Revision 1
Product Stewardship
Safe installation and use of shape
cutting equipment
IEC 60974-9, titled Arc Welding Equipment – Installation
and use, provides guidance in the safe installation and use
of shape cutting equipment and the safe performance of
cutting operations. The requirements of national and local
regulations shall be taken into consideration during
installation, including, but not limited to, grounding or
protective earth connections, fuses, supply disconnecting
device, and type of supply circuit. Read these instructions
before installing the equipment. The first and most
important step is the safety assessment of the installation.
The safety assessment must be performed by an expert,
and determines what steps are necessary to create a safe
environment, and what precautions should be adopted
during the actual installation and operation.
Procedures for periodic inspection
and testing
Where required by local national regulations,
IEC 60974-4 specifies test procedures for periodic
inspection and after repair or maintenance, to ensure
electrical safety for plasma cutting power sources built in
conformity with IEC 60974-1. Hypertherm performs the
continuity of the protective circuit and insulation
resistance tests in the factory as non-operating tests. The
tests are performed with the power and ground
connections removed.
Hypertherm also removes some protective devices that
would cause false test results. Where required by local
national regulations, a label shall be attached to the
equipment to indicate that it has passed the tests
prescribed by IEC60974-4. The repair report shall
indicate the results of all tests unless an indication is made
that a particular test has not been performed.
Qualification of test personnel
Electrical safety tests for shape cutting equipment can be
hazardous and shall be carried out by an expert in the field
of electrical repair, preferably someone also familiar with
welding, cutting, and allied processes. The safety risks to
personnel and equipment, when unqualified personnel are
performing these tests, may be much greater than the
benefit of periodic inspection and testing.
Hypertherm recommends that only visual inspection be
performed unless the electrical safety tests are specifically
required by local national regulations in the country where
the equipment is installed.
Residual current devices (RCDs)
In Australia and some other countries, local codes may
require the use of a Residual Current Devices (RCD)
when portable electrical equipment is used in the
workplace or at construction sites to protect operators
from electrical faults in the equipment. RCDs are
designed to safely disconnect the mains electrical supply
when an imbalance is detected between the supply and
return current (there is a leakage current to earth). RCDs
are available with both fixed and adjustable trip currents
between 6 to 40 milliamperes and a range of trip times up
to 300 milliseconds selected for the equipment
installation, application and intended use. Where RCDs
are used, the trip current and trip time on RCDs should be
selected or adjusted high enough to avoid nuisance
tripping during normal operation of the plasma cutting
equipment and low enough in the extremely unlikely event
of an electrical fault in the equipment to disconnect the
supply before the leakage current under a fault condition
can pose a life threatening electrical hazard to operators.
To verify that the RCDs continue to function properly over
time, both the trip current and the trip time should be
tested periodically. Portable electrical equipment and
RCDs used in commercial and industrial areas in Australia
and New Zealand are tested to the Australian standard
AS/NZS 3760. When you test the insulation of plasma
cutting equipment to AS/NZS 3760, measure the
insulation resistance according to Appendix B of the
standard, at 250 VDC with the power switch in the ON
position to verify proper testing and to avoid the false
failure of the leakage current test. False failures are
possible because the metal oxide varistors (MOVs) and
electromagnetic compatibility (EMC) filters, used to
reduce emissions and protect the equipment from power
surges, may conduct up to 10 milliamperes leakage
current to earth under normal conditions.
If you have any questions regarding the application or
interpretation of any IEC standards described here, you
are required to consult with an appropriate legal or other
advisor familiar with the International Electrotechnical
standards, and shall not rely on Hypertherm in any respect
regarding the interpretation or application of such
standards.