ABB S800 I/O - Page 59

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3BSE 020 923R101 49
• All who work on the installation must know the location of the main power
supply switch to the equipment and how it is operated.
• When the subsections of the process are checked and a test run has been
performed, interlocking links are to be checked by a responsible engineer.
All assembly personnel must be informed about test runs to be performed.
• Process technicians are to be present when testing and operating the process
device.
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• Avoid direct contact with the bus connector of the I/O modules.
• Always switch off the voltage before extracting a module which can not to be
exchanged with power applied, for example, processor units, extension cable
adaptors and extension cables, see Chapter 5, Maintenance. Wait a sufficient
time for the capacitors to discharge before removing a power sensitive module.
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This section describes where and how grounding is to be done in a cabinet or small
enclosures. You should be aware of the common $%%,QVWDOODWLRQ5 XOHV manual
which establishes the principals of grounding, knowing when an equipment,
a circuit or a cable shield should be grounded. It also gives alternative solutions
adapted to specific plant requirements.
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When cabinets are connected together, it forms a stable ground plane for all
equipment installed. The signal processing electronics in the modules as well as all
interference suppression for external signals is normally directly grounded to
chassis and plant ground.
Work with care when supply voltage is applied to the system. Voltages within the
cabinet can cause serious injury or death
Observe the following safety rules: