Technologies for safe material handling
With TRUNINGER you are on the safe side.
Our technologies are designed to make material handling as safe as possible and avoid putting workers at risk.
Failure of our systems is virtually impossible because we rely on redundancy that keeps up power at all times. By this, we are able minimize the risk of injury to your personnel while saving time as well as money along the way. Put your trust in TRUNINGER!
A vital troubleshooting tool to minimise your system down time
Similar in principle to the black box recorder found on most aircraft, the event log keeps track of all major system events, faults and most operator actions. Up to 4500 individual events can be stored in SmartPick’s non-volatile memory; this represents approximately 200 magnet load cycles for a typical system.
The information contained in the event log presents a detailed picture of a system breakdown that cannot be obtained by any other means; this makes the event log an invaluable troubleshooting tool. In fact there may be no need to call for a technician. With the aid of the event log many problems can be solved quickly via telephone or email.
Accessing the event log can be done wirelessly from a laptop at the factory floor level thanks to SmartPickTM’s built-in Bluetooth module, as shown below:
Figure 1: Accessing the event log via a Bluetooth link
A standard serial cable can be also be used instead of the Bluetooth link but this requires access to the crane gantry and SmartPick cabinets. Once the laptop is connected to SmartPick the event log can be easily stored in a file and e-mailed to a Truninger support centre for rapid analysis by a system specialist. Since the event data is stored in a standard text file, no special tools are needed to view the event log.
Inside the event log
All events logged have a unique event number and carry a date/time stamp; it is therefore possible to determine, to the nearest second, exactly when a particular event occurred. Events cover the following types of information:
- Magnet on/off cycles
- Magnet current and battery voltage
- Use of special features such as Partial Drop (order picking)
- Mains failures and battery switches
- Magnet lifting force selected during material handling operations
- Magnet and environment temperature
- State of crane interface signals
- System information: controller restarts, software versions, system id
- Changes to configuration data
Some examples: weak battery
The batteries play a critical role in the operational safety of a magnet system. Battery capacity is therefore tested every time the magnets are switched on and if the capacity is insufficient, power on is aborted.
The following event log extract shows an attempt to switch on the magnets when the voltage drop on the battery is too great. Note that events are normally displayed in reverse chronological order, the most recent event appearing first:
Event: 3398: 214 14:29:48 05.10 RB:chrg enabled 00000
Event: 3397: 145 14:29:44 05.10 Hoist lock OFF 00001
Event: 3396: 147 14:29:44 05.10 Travel lock OFF 00001
** Event: 3395: 012 14:29:20 05.10 RB:Bat test fail 01999
Event: 3394: 206 14:29:20 05.10 RB:bat voltage 00101
Event: 3393: 144 14:29:18 05.10 Hoist lock ON 00001
Event: 3392: 146 14:29:18 05.10 Travel lock ON 00001
Event: 3391: 213 14:29:18 05.10 RB:chrg disabled 00000
Event: 3390: 128 14:29:18 05.10 CB:VG ON 01000
The key events we see here are the following:
- Operator gives command to switch on a magnet (event 3390)
- Measured battery voltage just before battery test is 101 Volts (event 3394)
- Battery test fails because of excessive battery voltage drop (event 3395 data ‘999’)
The next example illustrates a slightly different battery test failure scenario (event 1695). Here we see that the measured current during the battery test was almost zero (100mA). This immediately suggests, not a problem with the battery itself, but a possible blown fuse.
** Event: 1695: 012 13:33:47 25.03 RB:Bat test fail 13001
Event: 1694: 206 13:33:47 25.03 RB:bat voltage 00114
Event: 1693: 144 13:33:37 25.03 Hoist lock ON 00001
Event: 1692: 146 13:33:36 25.03 Travel lock ON 00001
Event: 1691: 213 13:33:36 25.03 RB:chrg disabled 00000
Event: 1690: 128 13:33:36 25.03 CB:VG ON 24032
Example of operator mishandling
As most operator actions are logged it is also possible to identify operator handling errors. For example if a load dropped because an operator attempted to transport material using a very low lifting force, this will be visible in the event log. In the following scenario the operator was picking a stack of plates and reported that some plates dropped during the transport phase:
Event: 2583: 147 12:30:08 20.12 Travel lock OFF 00001
Event: 2582: 212 12:30:08 20.12 RB:swtch fl cfm 10240
'Event: 2581: 150 12:30:07 20.12 End hoisting 00000
Event: 2580: 148 12:30:07 20.12 Start hoisting 00000
Event: 2579: 150 12:30:06 20.12 End hoisting 00000
Event: 2578: 148 12:30:05 20.12 Start hoisting 00000
Event: 2577: 202 12:30:02 20.12 RB:new pl cfm 10240
Event: 2576: 143 12:30:02 20.12 CB:part load set 10001
Event: 2575: 202 12:30:02 20.12 RB:new pl cfm 10240
'Event: 2574: 143 12:30:02 20.12 CB:part load set 10002
Event: 2573: 202 12:30:01 20.12 RB:new pl cfm 10240
Event: 2572: 143 12:30:01 20.12 CB:part load set 10005
Event: 2571: 145 12:29:59 20.12 Hoist lock OFF 00001
Event: 2570: 139 12:29:59 20.12 PG power ON 40009
Event: 2569: 139 12:29:59 20.12 PG power ON 30009
Event: 2568: 139 12:29:59 20.12 PG power ON 20009
Event: 2567: 139 12:29:59 20.12 PG power ON 10009
Event: 2566: 199 12:29:59 20.12 RB:Bat test OK 00240
Event: 2565: 206 12:29:59 20.12 RB:bat voltage 00105
Event: 2564: 198 12:29:57 20.12 RB:Bat chrg OFF 00000
Event: 2563: 146 12:29:57 20.12 Travel lock ON 00001
Event: 2562: 144 12:29:57 20.12 Hoist lock ON 00001
Event: 2561: 128 12:29:56 20.12 CB:VG ON 10240
Although the load drop itself is not always visible in the event log, by knowing the approximate time of the incident, we can track the operator actions leading up to the load drop:
- Command to switch on magnet groups 1-4 (event 2561)
- Magnet groups 1-4 power on with pre-selected force level 9 (events 2567-2570)
- Operator reduces magnet force level to 5, then 2 and finally 1 (events 2572-2576)
- Operator starts hoisting, triggering automatic switch to full force (events 2578)
Sometimes the interpretation of information contained in the event log can depend on certain configuration settings. In this particular case, the customer had activated in his configuration (not shown here) a feature called Proportional Full Load which adjusts the full load force of the magnets (normally 100%) in proportion to the last partial lifting force selected.
Conclusion: the fact that force level 1 was selected (event 2576) just before switching to full load meant that only approximately 20% of the full lifting force was applied during the transport phase of the operation. The load was therefore not safely secured and explains why some of the plates fell.
An important secondary function of the event log is to collect statistics. From the data contained in the event log it is possible to generate graphs and charts for visualising certain aspects of magnet usage. In the example below (cf. Figure 2) we can see, for a specific system, how magnet power off times varied with each load cycle. This analysis could conceivably be used to help optimise material handling processes in a warehouse or steel production line.
Figure 2: Demagnetization times of a magnet
1. What is redundancy?
Electrical controls are built using a whole bunch of sub-systems each having a certain potential of failure. To provide safety of the system in case of a single sub-system failure, safety relevant subsystems are built double, generaly refered to be “redundant”. Two sub-systems work on the same task and also cross-check each other to make sure, both systems work fine. Two redundant systems do not add much to safety, if failure of one system is not detected. Therefore, redundancy, cross-check and safety relevance are core elements of safety class 3 design concept also referred to in international standardization document DIN-EN 954-1.
2. Standard redundant components
The concept of redundancy is a central feature built-in Truninger magnet controller SmartPickTM. All safety relevant sub-systems are duplicated according to the safety class 3 standard.
The following sub-systems are covered:
- Two power sources- mains and backup battery
Backup battery capacity is designed to maintain safe operation for at least 20 minutes in case of mains power failure.
- Two current sensors—two associated cross-checked signal processing units
Failure of one sensor will be detected and triggers a switch over to battery operation and system lock (magnet can be switched OFF but no more ON).
- Two power drives—AC/DC & DC/DC
One drive dedicated to mains power AC/DC and one drive dedicated to battery power DC/DC. Failure of power electronics in any drive such as IGBT transistors will cause the second drive to take over and also lock the magnet system.
- Two controllers built in different hard and software
Any failure of the SmartPickTM main controller will hand over the control task to the slave controller SafePickTM.
- Two low voltage power sources
Each of the two controllers is equipped with individual low voltage power sources. Such power sorces are continously cross-checked and both are battery backuped.
Optional redundant electric circuits
Most often, the power lines from the controller to the magnet are considered safe and therefore not built redundant. However, in some harsh environments, cables and cable drums can not be considered safe.
If required, two independent electric power circuits for one single magnet can be realised. Two cables, two cable drums, two electric coils in the magnet and two power modules PowerPickTM build up such independant electric power circuits. Even a short cut at any location of one circuit will not stop this system from operating.
Figure 1: Redundant Magnet Controller SmartPickTM
Module SmartPick (SP), Nr. 1 CPU controlling AC/DC drive, signal inputs, redundant low power supply
Modul SafePick (SA), Nr. 2 CPU contolling DC/DC drive, battery charger, battery supervision / maintenance (autoamtic capactiy test)
|PP 1 & 2|
Modul PowerPick (PP), generates safe DC Power for magnet uniting mains- and battery power drive
Modul InfoPick, graphic display informing the operator and staff on the ground visuallyand acoustically about the state of magnet system
Two operation units can be connected to SP, if one of operation unit fails, another unit can be used as backup
Redundant magnet with double coil each connected to one PP module, this results in safe power supply keeping up sufficient magnet force in case of any power circuit Coil failure
Figure 2: Magnet system on overhead crane
Figure 3: Redundant magnet system for bar bundles
Standardized, redundant components
The concept of redundancy is a central function of all electrical subsystems of TRUNINGER lifting magnet systems.
The first level of redundancy covers the failure of the mains supply and/or the failure of the main processor module. This function is standard for the majority of the systems and is achieved through the following components:
- SafePickTM module:
automatically switches to backup battery operation in the event of a mains power failure and also allows the magnets to be switched off if the main SmartPickTM control module has failed.
- Backup battery:
Ensures power supply to the magnets for at least 20 minutes with the load suspended in the event of a power failure.
Option: Total redundancy
If required or desired, we build magnet systems with total redundancy, using multiple redundant subsystems. Figure 1 shows a typical overhead crane with a magnet system for coil transport.
Figure 1: Magnet system with total redundancy
The most important additional redundant subsystem is the double line feed from SmartPickTM to the magnets.
The redundant components are:
- Two PowerPickTM modules.
- Two sets of flat cables.
- Two cable reelers.
- Two independent coils inside the magnet.
This arrangement forms two completely independent end-to-end power circuits which guarantees safety of the load even in the event of partial or complete failure of one circuit.
Also a redundant operator control sub-system ensures that the magnets may be operated from a backup pendant if the radio control unit or radio receiver are faulty.