Hirschmann overload protection certified for gantry cranes28 March 2017 by Daniel Searle
TÜV Austria has certified Hirschmann’s cSCALE trueSafety control under the EN 15011 standard for bridge and gantry cranes, as well as under EN 13849, which covers design principals for safety-related control systems, and EN 62061, covering functional safety of electronic control systems.
The trueSafety controller is the successor to PSV overload protection systems developed by Hirschmann’s predecessor company, PAT & Krüger.
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.
Parametrisation, calibration, and checking are much easier than with PSV, Hirschmann explains, thanks to a user-friendly, browser-based service tool. It enables both on-site work and remote maintenance.
The cSCALE controller integrates smoothly into the overall control architecture, the company adds. 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.
The certified system meets all of the requirements for overload protection according to EN 15011:2011. Overloads are reliably detected to ensure timely system cut-out in critical situations while complying with PL d, the appropriate performance level defined in the standards. 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, cut-out 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 such as the selected operating mode, analog measurement values, and calculated values such as 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 spreadsheet software using a memory stick.
The proven cSCALE controller supports up to eight different operating modes, such as for different spreads or grippers, according to PL d. A key switch-protected, PL d category 3-compliant servicing mode is also integrated.