Gantry and bridge cranes need to be able to move heavy loads easily and safely. Hirschmann MCS based in Ettlingen, Germany, a market leader in controllers and sensors for these applications, has developed and obtained certification for an innovative complete overload protection concept.
Yardena Hemmann, Marketing Communications Manager, Mobile Machine Control Solutions at Hirschmann Automation and Control GmbH, explains more.
PSV overload protection devices (originally introduced by PAT & Krüger, now Hirschmann MCS) have been a mainstay for decades. Recently, however, they became obsolete with the advent of the new cSCALE trueSafety controller. The individual cSCALE components are perfectly harmonized with the fSENS force sensors. Both were recently certified under the latest versions of the EN ISO 13849 and EN 62061 standards as well as the EN 15011:2011+A1:2014 standard for bridge and gantry cranes, which covers all safety functions and sequences.
Crane Manufacturers Benefit from Simple Implementation
The certified complete overload protection concept saves crane manufacturers and operators the expense and trouble of obtaining individual certificates when equipping or re-equipping cranes. All of the components involved are completely compatible. Parametrization, calibration, and checking are much easier than with PSV, thanks to a user-friendly, browser-based service tool. It enables both on-site work and remote maintenance. Everything is password-protected with flexibly assignable access privileges. The cSCALE controller integrates smoothly into the overall control architecture. Modbus, TCP/IP, CANopen, Profibus-DP, and ProfiNET I/O communication interfaces are available. The sensors of the fSENS series and the cSCALE controllers are robust, require a minimum of maintenance, and work reliably under harsh environmental conditions.
Benefits for Users: Maximum Safety and Control
The certified system meets all of the requirements for overload protection according to EN 15011:2011. Overloads are reliably detected to ensure timely system cutout in critical situations while complying with PL d. This can happen in either of two different ways: indirectly with a delayed cutout to compensate for hysteresis, or immediately if the weight involved is greater.
A large number of other functions can also be optionally enabled. They include a limit switch that protects hoists by blocking their upward motion when triggered (complying with PLd category 3), limiting wire rope layers in winches by blocking their downward motion, horizontal and vertical monitoring of unbalanced loads, cutout when the load falls short of a defined minimum, monitoring of proper functioning according to PL d, and monitoring of loads on individual ropes according to PL d.
Once the system has been configured, it ensures maximum safety. Audible and visual alarms are activated in compliance with PL d, including a slack cable warning, sirens, and lamps.
The comprehensive data logger shows error and event messages, status information (e.g. the selected operating mode), analog measurement values, and calculated values (e.g. total and individual loads). Data are stored at regular intervals and after certain events.
Reports are also compiled, containing data from the operating hour counter, the stroke counter, and the timespan load counter. Strokes are recorded in different load ranges.
These values are continuously recorded for at least 30 days and are easy to import into Excel using a memory stick.
The proven cSCALE controller supports up to eight different operating modes (e.g. for different spreads or grippers) according to PL d. A key switch-protected, PL d category 3-compliant servicing mode is also integrated.
Emphasis on Practical Relevance
The engineers of Hirschmann MCS know what matters, and have therefore designed the solution so it can be flexibly parametrized for a wide variety of requirements. They include:
• Support for between one and eight redundant force sensors
• Digital or analog height correction, i.e. correction of the load display to compensate for the angles of the stay ropes
• Adjustable cutout points
Summary: an Ideal Solution from One Source
This unique new, EN 15011-compliant overload protection system from Hirschmann MCS takes the time-proven PSV to a new level, thus meeting the current needs of manufacturers and equippers of bridge and gantry cranes. A browser-based service tool permits straightforward, user-friendly setting of parameters. The offered modules are robust enough to permit maintenance-free use in extreme environments, and the cSCALE controller is easy to integrate into existing crane control systems.
Hirschmann Mobile Machine Control Solutions (MCS) is a business unit of Hirschmann Automation and Control GmbH and belongs to the U.S.-based Belden Group.
Hirschmann MCS is a world market leader in safe load indication for telescopic and lattice-boom cranes and a specialist in controllers for mobile work machines. As a leading system provider, the company continually sets new standards in innovative automation platforms for mobile applications in harsh environments.
Drawing on experience and expertise gained during more than 40 years, the team of Hirschmann MCS enables communication between humans and machines.
At facilities in Germany, the United States, and China, 450 employees develop, optimize, and produce products, systems, and solutions. These comprise both software and hardware in the form of sensors, controllers, and consoles for mobile machines and applications.
Hirschmann MCS is a reliable, innovative, and flexible partner that provides topnotch technology, quality, and service while making sure that its components and solutions comply today with tomorrow’s differentiated safety requirements and general standards.