All cranes are constructed based on a theoretical lifetime. This lifetime is calculated using the nominal load, nominal use and a theoretical usage concentration. Once this lifetime is up, the crane is recommended to be refurbished and critical components have to be replaced.
With an accurate record of all movements and loads, the function block assists the user in choosing the right time for maintenance. In the case of many movements with a high load, it is possible to plan maintenance work before a component breaks down and eliminate long down times. When loading is occasional it is possible to postpone maintenance, leading to a longer lifecycle and effective maintenance costs.
NOTE: The function block retains the recorded data despite shut down or power cut to the controller. For a proper retention of values, a working battery in the controller is required for those platforms which have battery backed memory.
Monitoring data storage is a function for collecting and monitoring the crane's operational data to improve handling efficiency:
oIt allows monitoring of the machine usage under normal and abnormal conditions. All movements of the crane are monitored.
oUsage rates are tallied and an alarm is signaled when the system or individual components require maintenance.
oAbnormal conditions such as detected alarms are stored individually.
The function is applicable to the following types of cranes:
oIndustrial cranes (trolley, bridge and hoisting movement)
oConstruction cranes (trolley, slewing and hoisting movement)
The Monitoring data storage consist of set of a function blocks for EcoStruxure Machine Expert controller which is dedicated to collect operational and detected alarm data from the crane. Following are the function blocks of Monitoring data storage:
oStatisticDataStorage_2
oAlarmDataStorage_2
oMaintenanceDataStorage_2
These function blocks are using an internal function to get the system cycle time for recording the events.
StatisticDataStorage_2 Function Block
The StatisticDataStorage_2 function block analyzes the crane movements and records the necessary information including:
oOperation hours of the hoist, the trolley, slewing and traveling
oNumber of the hoist, trolley, slewing and traveling operations
oNumber of backtracking operations of the hoist, trolley, slewing and traveling
oNumber of pulsating operations of the hoist, trolley slewing and traveling
Backtracking: If different direction movement commands (forward and reverse) are given within a two seconds period, a backtracking event is recorded and a count is incremented by one. If both forward and reverse movement commands are received simultaneously, no backtracking operation is recorded.
Pulsating: If the same direction movement command (forward or reverse) is given within a period of two seconds, a pulsating event is recorded and a count is incremented by one.
For detailed description refer to the function block description.
AlarmDataStorage_2 Function Block
The AlarmDataStorage_2 function block records the alarms detected in the system. Alarm data storage is involved in the following functions:
oNumber of alarm events detected
oDuration of the detected alarm event
oHistory of the detected alarm event, (time and date of occurrence and duration of the detected alarm)
oThe number of hours since the last detected alarm event
For detailed description refer to the function block description.
MaintenanceDataStorage_2 Function Block
The MaintenanceDataStorage_2 function block is used to record statistical information about the hoist drive and calculates the remaining hours before maintenance, including:
oHours spent by the hoist drive working with the actual load
oRemaining hours that the hoist drive can work with the actual load
oHours 300 class of hoist (amount of hours with more than 300 operations per hour)
oHours 600 class of hoist (amount of hours with more than 600 operations per hour)
For detailed description refer to the function block description.
PasswordDataStorage Function Block
The PasswordDataStorage function block validates different passwords and indicates a valid password at the output. The block is usually used in combination with the other blocks and protects the reset input of the other blocks against unauthorized reset.
Why Use the Monitoring Data Storage Function?
The Monitoring data storage function is essential for the following reasons:
oCollection and monitoring of operation data
oCalculation of effective maintenance intervals
oInspections and revisions of the cranes are necessary according to applicable safety
oIncreased demand for periodic and preventive maintenance
Solution with the Monitoring Data Storage Function
The function uses internal real time clock of the EcoStruxure Machine Expert controller to time stamp the events such as alerts or detected alarms.
