The Schmersal Group gradually extends its range of switchgear for explosion-endangered areas; at Automatica, the Group presented two safety-monitoring modules of the PROTECT SRB series, which are characterised by their red front cover as well as by the sensors, connected as additional equipment for installation in the Ex zones 1/2 (gas Ex) and 21/22 (dust Ex), which have protection class Ex I, i.e. they are suitable for monitoring the “intrinsic safety”. In addition to that, the SRB safety-monitoring modules can also be installed in explosive atmospheres due to the presence of gas of Zone 2.
The SRB 101 EXi module is designed, amongst other things, for the safe signal processing of an emergency stop command device or a safety switch installed on the safety guards of machinery and plants. With its mounting width of only 22.5 mm, it can be smoothly installed in the control cabinet and despite its compact size, it features many interesting comfortable safety functions. The control for instance detects wire breakage, cross-wire shorts and earth leakages in the monitoring circuits and LED’s signal the current operating status. In case of a dual-channel signal processing in combination with the sensor technology, Performance Level “e” to DIN EN ISO 13849-1 can be achieved.
Besides the safe signal processing, the safety-monitoring module is equipped with a safe switch-off level with redundant structure. Through the self-monitoring circuits, hazardous movements can be switched off by means of the available enabling circuit, without needing additional measures with regard to the functional safety.
The SRB 200 EXi, which however has two enabling circuits, features the same functions. Both safety-monitoring modules are optionally available as version with automatic reset function and trailing edge. In this case, the SRB 101 EXi or the SRB 200 EXi reactivates a safety function, as required, only when a reset button has been pushed and released. This edge detection is an additional safety measure preventing any unexpected restart in case the button is manipulated or defective.
The Schmersal Group offers a comprehensive range, e.g. safety switches, safety sensors and position switches with safety function, for use in the gas Ex zones 1 and 2 as well as the dust Ex zones 21 and 22. New products here are, amongst other things, the robust position switches with safety function of the EX-T 335 series with metal enclosure. As they can be equipped with different actuators, they are suitable for various applications.
The Schmersal Group offers Ex i safety-monitoring modules monitoring the intrinsic safety for the signal evaluation of ATEX-compliant safety switchgear.
