The use of the compact and freely configurable STB / STW fitted on top
hat rails allows early, safe and reliable recognition of hazards that
could lead to injury, environmental damage or to the destruction of
production equipment and goods.The primary task of safety temperature
limiters is the reliable monitoring of technical heat processes and
switching equipment to an operationally safe condition in the event of a
The devices come with approvals as per DIN EN 14597, SIL, PL (performance level ), UL, and GL, which shorten the users' own approval processes. All calculation values required for this purpose, for instance MTTfd, PFD, SSF, DC, λ dd, λ du in FIT are made available in the familiar manner.
The high standards of DIN EN 61508 or DIN EN 13849 are met by a device concept, the 1oo2D structure of which guarantees the safe recognition of errors and faults. As such, it can also be used for applications subject to the new 2006/42/EC machinery directive. Safety and reliability were the key features during the development of the devices. Simple commissioning/start-up was also a focal point.
In conjunction with the keyboard, the brilliant and clearly structured display with plain text display and background lighting ensures easy configuration directly at the device. The clear menu structure allows the user safe use of the device, which shortens the commissioning period. All safety relevant process variables are displayed; the most important functions are represented by easy-to-understand pictographs.
A mini USB plug at the front permits configuration through a PC or laptop. Light diodes show whether or not the device is functioning perfectly or if a pre-alarm or a limit value alarm has been triggered. The measuring input with a large number of linearizations can be freely configured for RTD temperature probes and thermo-couples and for current measurements. In the event of faults/errors, two relay outputs (pre-alarm and limit value alarm) switch the process into a safe condition. With regard to the limiter function, the device is released again by an internal or external unlocking key. Process values can be transmitted to a recording device or a controller or a higher-ranking control system via the serie's analog output.
Additional features, such as a password controlled access and a settable level locking increase operating safety and process reliability. Voltage supplies of AC 110...240V (-15%/+10%), 48…63Hz or AC/DC 20...30V, 48..63Hz are available.