One safety module will replace dozens of relays

The UK safety specialist Smartscan has developed a module which, it claims, will revolutionise safety relay technology. By using plug-in memory chips, the "character" of the relay module can be tailored to suit a variety of applications, such as emergency stops, two-hand controls, rundown timers, zero-speed monitors, and safety gate switch monitors. This allows a single module to replace 20 or more different conventional safety relays.

Mike Hudson, UK sales manager for the Corby-based firm, believes that the new controller - called Integron - could pose a real threat to established suppliers of safety relays, most of whom have large ranges of products with dedicated functions. "This will frighten a few people," he predicts.

Hudson speculates that the reason that no other safety supplier has tried this approach before is that they have invested large amounts in their existing ranges. Until now, Smartscan has focused on light curtains and has not offered safety relays. "We have no market to protect," says Hudson. "We are new to the game."

He predicts that new system could rapidly become Smartscan`s biggest business.

As well as offering the plug-in chips with pre-programmed safety functions - such as press controls, safety mat and edge monitors, and robotic cell controls - Smartscan will also program the chips to customers` requirements. Alternatively, users can configure inputs and outputs for themselves using a simple graphical software program based on standard ladder logic.

The controllers have two independent microprocessors, which can exchange data dynamically and monitor each other. They can provide safety and operational control simultaneously. Their inputs and outputs can be used individually, or paired to allow cross-monitoring.

The controllers provide safety integrity to Category 4 of EN954-1, or SIL 3 of IEC 61508.

The basic version of the controller, the Integron 20, offers 16 inputs and four outputs and is designed to replace up to eight conventional safety relays. For more complex applications, the Integron 52 provides up to 36 inputs, 16 outputs, 32 timers, four counters and two speed monitors. This controller can log safety data and thus help users to comply with the requirements of EN 61508.

Following field trials of the new devices over the past year, Smartscan is planning to launch them in January, initially in the UK. Hudson says that prices will vary according to the complexity of the chips, but adds that the safety controllers will be priced to compete "head-to-head" with conventional safety relays. He points out that there will be savings in terms of panel space requirements, wiring, commissioning times and stock levels.