Light curtains optional functions as listed in annex a of iec 61496 part 1 must comply with annex a requirements.
Light curtain muting requirements.
Safety light curtains are an advanced method of safeguarding personnel around many hazardous machines.
When enabled a function block is purple with a 3 second count down timer.
Muting shall be desabled as soon as the light curtain is cleared and not later than 4 seconds max.
Muting allows the stock to bend and the operator to move through the light plane without stopping the press brake slide.
Next lets test the mute function.
Muting for most of the stroke is required since the tooling will interrupt the light curtain during normal stroking of the press.
Safety related stop of hazardous motion initiated by a light curtain.
Also the status output for the mute light changes to green.
Muting light curtain monitoring relays allow the automatic temporary suspension of the safety function if certain conditions are met.
The terms muting and blanking are frequently used incorrectly.
Two sensor l type muting of a light curtain.
The timer monitoring the 4 seconds shall be a safety related item.
Safety function requirements interrupting the light curtain stops and prevents hazardous.
Emergency stop of hazardous motion initiated by an e stop button.
Our standard s difficulty here is that 1910 217 c 3 iii d allows muting on the upstroke and this application requires muting during over a much longer portion of the cycle.
This system executes a stop category 0 stop.
From the instant the first of the two muting sensors is cleared.
After 3 seconds the status output and mute function turn off.
First we test the safety light curtain and latch reset with mute off.
Also called light screens optical guards and presence sensing devices safety light curtains offer freedom flexibility and reduced operator fatigue when compared with traditional guarding methods such as mechanical barriers sliding gates and pull back restraints nbsp.
Muting of a light curtain.
Emergency stop of hazardous motion initiated by an e stop button.
In material handling applications material is allowed to pass through the protective field without shutting down the machine.
At this point the light curtain is muted with the die no more than 1 4 above the workpiece or automatically turned off.
Light curtains must be properly integrated into the machine.
This post will help clarify the difference between the two so the correct safety light curtain functionality is chosen and the machine runs safely.
Emergency stop of hazardous motion initiated by a light curtain.
The motion is allowed to coast to a stop.