Broderson RT-400-A, Operation And Maintenance Manual

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2-17
CRANE CAPACITY
Before lifting loads, the operator must read the Crane Capacity Chart and adhere to the
load capacities and radii of handling stated in the chart. The information provided on this
chart is based on stability, structural strength and hydraulic capacity.
To operate the crane safely, the operator must know the weight of the load and handling
devices , and the radius of the lifting operation. The crane must not be loaded beyond the
specifications of the capacity chart except for test purposes as provided in ASME B30.5. The
person responsible for the lift must be sure that the load does not exceed the crane ratings at
any radius or position at which the load may travel during the entire lifting operation. The
weights of the hooks, blocks, downhaul weights, slings, and other handling devices must be
added with the load.
Be aware that one outrigger may lift off the ground while operating on outriggers at less than
Rated Capacity. This is considered normal if the load is mainly over the opposite corner at
the time. The loading on the outrigger closest to the hook load will increase substantially.
Loading on the outrigger in the opposite corner will decrease. Flexing in the chassis can
cause the opposite corner to lift slightly.
The Rated Capacity Limiter on the crane is intended to assist the operator in estimating
loads, measuring load radii and to alert the operator to impending overload conditions. The
use of the Rated Capacity Limiter does not replace the requirements of the preceding section.
Verified weights and measured radii must take precedence over the Rated Capacity Limiter
readings.
The Rated Capacity Limiter displays a load, load radius and boom angle that are obtained
from electronic calculations using readings from pressure, length and angle sensors. These
readings cannot be exact and should be treated as estimates.
Be aware that the electronic and mechanical components cannot be 100% fail-safe. Do not
consider the system as a substitute for good judgment, training, experience or accepted safe
operating practices. The operator is solely responsible for operation of the crane.
Setting the Rated Capacity Limiter for the proper configuration of the crane is necessary
before starting a lift. If incorrectly set, the system will not alert the operator to an impending
overload, possibly resulting in the loss of life or destruction of property. If the Rated Capacity
Limiter is inoperative or malfunctioning, repair or recalibration of the unit must be done as
soon as reasonably possible. The person responsible for lifts must establish procedures for
determining load weights and radii and conduct the lifts according to safe operating practices.
The Rated Capacity Limiter is designed to stop some crane functions at the limitations of the
capacity chart. These are: BOOM LOWER, TELESCOPE EXTEND, and HOIST RAISE.
Great care must be exercised when handling a load near capacity or near a two-blocking
condition. If the boom is being lowered or swung, the load will tend to swing if the Rated
Capacity Limiter stops the boom movement. If the load is moving too fast, the sudden
stopping by the system can cause dangerous load swinging which can cause death or injury
to personnel or property damage by impact with the load or by the crane tipping.
W A R N I N G
The Rated Capacity Limiter can suddenly stop the BOOM LOWER, TELESCOPE
EXTEND, and HOIST RAISE functions, causing the load to bounce or swing. Use great
care when handing a load near capacity limits or near a two-blocking condition.