APPLICATIONS OVERVIEW 11 12 APPLICATIONS OVERVIEW
Cross-Beam Muting – outfeed zones only Figure 2 Cross-beam muting (outfeed only system), see figure 2, is selected for applications where a safety light curtain is required to prevent personnel access into a machine at an outfeed zone – where the palletised load passes from the danger area into the industrial safe area. On no account should a cross-beam muting, outfeed zone system be used for safeguarding an infeed zone. The cross-beam muting, outfeed zone system has a high level of safety integrity as the muting beams (M1 and M2) are positioned inside the danger area and out of reach from interference by personnel. If a pallet stops in a position blocking the mute beams with mute enable connected the light curtain will stay in a mute condition for 15 minutes. All 8000 Series light curtain can very simply be configured for cross-beam muting. The system shown in Fig. 2 can be used only for safeguarding outfeed zones. Select an 8000 Series light curtain with a detection height to suit the specific application plus, a bolt-on, fullyintegrated mute sensor kit type (083-002). The mute sensors (M1 and M2) inside the muting module are positioned approximately 210mm apart, the beams cross as shown. To maintain the correct sequence of operation of the safety system it is a requirementthat both mute initiating beams be interrupted by the pallet load prior to it entering the detection field of the light curtain. When the trailing edge of the pallet load ‘clears’ the mute beams it has approximately 0.2 to 7 seconds to ‘clear’ the sensing field of the light curtain. If this time is exceeded the safety system will trip.In some applications there may be a requirement to position mute sensors in a wider cross-beam configuration than that offered from the sensors inside the mute module. In such cases mute sensors for mounting externally can be provided. The polarised retro-reflective infra-red sensors come complete with 1.5m cable and a plug that connects directly into the receiver column of the Smartscan 8000 Series light curtain. Two polarised retro-reflective sensors, type (083-004) are required for correct operation of the cross-beam muting function.Sometimes palletised loads can be very much less in width than the industrial conveyor width. Also, the load may not be centralised on the conveyor or, the loads are unevenly stacked. They may be miss-shaped or, there may be large variations between each load, in both profile and volume. In such cases the cross-beam muting configuration may not be appropriate and parallel beam muting should be considered.All 8000 Series light curtains can very simply be configured for parallel beam muting. The system can be used for safeguarding both infeed and outfeed zones, or, zones where products are required to pass in either direction through the light curtain. 8000 SERIES8000 SERIES