Reset Alternatives

Reset

On the servicing side (i.e. the side/sides where there is an operator who moves parts in and out) there shall be a separate reset function for the light curtain. If there are several light curtains (e.g. on the front and back) there shall be one for each. If the light curtain is actuated during a dangerous movement, the press should not be able to restart without being reset. During engagement after the end of the cycle no reset is needed.

For a light curtain which is placed as protection on both sides which are not servicing sides, there shall be a reset button which always needs to be activated after an engagement.

Supervised Manual Reset

When a light curtain/light grid is interrupted it will give a stop signal to dangerous machines within the risk area it protects. For a new start of the machine the light curtain/light grid has to be reset. This is done with the reset button (Figure 1) which is placed where it cannot be reached from within the area which is protected. There are high requirements on the reset function—neither a short circuit nor a component fault shall give automatic reset. When the reset button has been affected the outputs are activated and the machine can initiate.

Automatic Reset

Automatic reset can only be used when it is impossible to get between the safety light curtain and the hazardous pinch point. When the operator removes his hands from the protective field the dual safety outputs will energize starting the next machine cycle immediately.

Pre-Reset Solution

If the machine start button is not located such that you have a clear view of the entire work area, additional safe guards must be used. Typical devices include Safety Laser Scanners, Safety Mats and Horizontal Safety Light Curtains.

The Focus Safety Light Curtain addresses this requirement without costly additional safety devices. By selecting the Pre-Reset mode through the Focus Receiver’s internal dipswitches, you satisfy the primary requirement for accidental resets. The Pre-Reset must first be cycled, which gives a clear view of the work area, then no longer than 7 seconds later the Final Reset must be cycled.