Light barrier cuts cost of machinery safety

Paul Boughton

It has been estimated that ensuring operator safety accounts for between 20 and 50 per cent of the cost of installing industrial automation.

To help reduce this expense, Scientific Technologies (STI) is introducing new, economical access guarding.

The PA4600-BB entry/exit access guarding device is a cost-effective yet powerful way of controlling access to hazardous areas like robot cells, textile machinery, packaging machines and automated warehouses.

The PA4600-BB is a Type 4 multiple-light-beam device, consisting of a transceiver and a reflector column, that is designed to be quick and easy to install. The precision optics in both the transceiver and reflector unit make alignment very straightforward and reduce the possibility of optical short-circuits.

Front panel access to the selector switches allows users to quickly customise configurations as required, and the LED displays allow access to the comprehensive monitoring and on-board diagnostic capabilities. Electrical connections for the PA4600-BB are kept as simple as possible to minimise installation time.

MPCE (machine primary control element) monitoring is also included as standard, which ensures the final switching device integrity of both the PA4600-BB and the machine it safeguards. If a fault is detected in either PA4600-BB or in the machine's switching control, an emergency stop is activated automatically. Separate scan codes eliminate cross-talk with adjacent PA4600-BB systems, which allows multiple devices to be used together for maximum area protection.

Depending on specific application requirements, the PA4600-BB generates two beams spaced either 500mm or 600mm apart to provide torso detection. Operating on a 24V dc supply, the two 625mA solid-state safety control output signals are fully compatible with a wide range of industry-standard safety relays. The safety control output signal can be used as the primary switching mechanism or as a means of actuating more substantial or force-guided switching devices. An operating range up to 8m and response time as low as 16ms makes PA4600-BB an excellent choice for entry/exit guarding.

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