Manitowoc NBT60XL, Руководство оператора

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NATIONAL CRANE
Published 11-01-2020 Control # 710-00
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NBT60XL OPERATOR MANUAL SAFETY PRECAUTIONS
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United States OSHA regulations require a flagman when
operating in close proximity to energized power lines.
Appoint a reliable and qualified signal person, equipped with
a loud signal whistle or horn and voice communication
equipment, to warn the operator when any part of the
equipment or load moves near a power source. This person
shall have no other duties while the equipment is working.
Tag lines should always be made of non-conductive
materials. Any tag line that is wet or dirty can conduct
electricity.
Do not store materials under power lines or close to
electrical power sources.
Electrocution Hazard Devices
The use of insulated links, insulated boom cages/guards, or
proximity warning devices does not assure that electrical
contact will not occur. Even if codes or regulations require
the use of such devices, failure to follow the rules listed here
may result in serious injury or death. You should be aware
that such devices have limitations and you should follow the
rules and precautions outlined in this manual at all times
even if the equipment has these devices.
Insulating links installed into the load line afford limited
protection from electrocution hazards. Links are limited in
their lifting abilities, insulating properties, and other
properties that affect their performance. Moisture, dust, dirt,
oils, and other contaminants can cause a link to conduct
electricity. Due to their capacity ratings, some links are not
effective for large equipment and/or high voltages/currents.
The only protection that may be afforded by an insulated link
is below the link (electrically downstream), provided the link
has been kept clean, free of contamination, has not been
scratched or damaged, and is periodically tested (just before
use) for its dielectric integrity.
Boom cages and boom guards afford limited protection from
electrocution hazards. They are designed to cover only the
boom nose and a small portion of the boom. Performance of
boom cages and boom guards is limited by their physical
size, insulating characteristics, and operating environment
(e.g. dust, dirt, moisture, etc.). The insulating characteristics
of these devices can be compromised if not kept clean, free
of contamination, and undamaged.
Proximity sensing and warning devices are available in
different types. Some use boom nose (localized) sensors
and others use full boom length sensors. No warning may be
given for components, cables, loads, and other attachments
located outside of the sensing area. Much reliance is placed
upon you, the operator, in selecting and properly setting the
sensitivity of these devices.
Never rely solely on a device to protect you and your fellow
workers from danger.
Some variables you must know and understand are:
• Proximity devices are advertised to detect the existence
of electricity and not its quantity or magnitude.
• Some proximity devices may detect only alternating
current (AC) and not direct current (DC).
• Some proximity devices detect radio frequency (RF)
energy and others do not.
• Most proximity devices simply provide a signal (audible,
visual, or both) for the operator; this signal must not be
ignored.
• Sometimes the sensing portion of the proximity devices
becomes confused by complex or differing arrays of
power lines and power sources.
Do not depend on grounding. Grounding of the equipment
affords little or no protection from electrical hazards. The
effectiveness of grounding is limited by the size of the
conductor (wire) used, the condition of the ground, the
magnitude of the voltage and current present, and numerous
other factors.
Electrical Contact
If the equipment should come in contact with an energized
power source, you must:
1. Stay in the equipment cab. Do not panic .
2. Immediately warn personnel in the vicinity to stay away.
3. Attempt to move the equipment away from the contacted
power source using the equipment controls which may
have remained functional.
4. Stay in the equipment until the power company has been
contacted and the power source has been de-energized.
No one must attempt to come close to the equipment or
load until the power has been turned off.
Only as a last resort should an operator attempt to leave the
equipment upon contacting a power source. If it is absolutely
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