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Safety first for new pushbutton range

Edited by the Engineeringtalk editorial team Mar 24, 2004

The Allen-Bradley 800F range of pushbuttons offers OEMs and panel builders maximum flexibility in the most demanding environments, without compromising safety.

The Allen-Bradley 800F range of pushbuttons offers OEMs and panel builders maximum flexibility in the most demanding environments, without compromising safety.

Combining the quality expected from Allen-Bradley products with unique safety features, the 800F meets all major international standards, including CCC approval for the emerging Chinese market, and is suitable for industrial applications throughout the world.

The 800F also complies with the new Restriction of Hazardous Substances (RoHS) Directive - legislation that, from July 2006, bans metals such as lead, mercury and cadmium from use in electrical products.

Easy to install and available in a variety of colours and functions, the pushbuttons include an innovative self-monitoring contact block for increased emergency stop protection, instantly cutting power to equipment.

Its unique design maximises protection through an integral fail-safe mechanism that ensures contacts do not remain closed when the stop button is pressed - even if the equipment develops a fault.

For additional safety, rigid teeth are incorporated inside all 800F selector switches to lock the mechanism, ensuring that the teeth do not get stuck between positions and that they are unaffected by shock or vibration.

Spring clamp or screw termination contact blocks keep installation simple, resulting in both time and cost savings: the snap-fit parts removing the need for tools when fitting the latch or contact blocks, and a rotating collar allows single-handed latch removal.

Colour-coded contact block plungers also make circuits easier to identify and an antirotation tab accurately aligns components, eliminating operator error and legend plate rotation.

These fitting options allow true single person installation, helping to reduce expensive labour costs.

Up to six contact blocks (electrical circuits) are available in most installations, enabling a wide range of switching applications without the need to go into more complex control switch options.

The new range features Rockwell Automation's trademarked QuadConnect contact block for low voltage switching.

Unlike conventional contacts, QuadConnect is extremely sensitive and responsive, and ideal for low voltage applications from 17V, 5mA down to 5V, 1mA - particularly for direct interfacing with state-of-the-art electronic devices.

Rated to IP66, advanced sealing techniques also maximise corrosion resistance and protect against dust and high-pressure water jets - a single range for different environments.

Interchangeable plastic and metal components further increase flexibility, allowing users to adapt the pushbuttons for a specific application.

A variety of high-quality latches, contact blocks and light emitting diodes are available to meet all OEM and end user requirements - whatever the application or space restrictions.

This new flexible, low profile design allows any operator component to be combined with any back-of-panel component, simplifying maintenance and replacement.

Users can also choose from a selection of LED options to light indicator lamps and illuminated versions of the selector switches and pushbuttons.

Available in 24V AC/DC, 120V AC and 240V AC, LEDs use less power and emit less heat than filament lamps, and are resistant to shock and vibration.

The integrated LEDs have an extended lifespan of around 100kh compared with only 5kh for traditional filament lamps.

Laser engraving allows the pushbutton caps and diffusers to be customised with text or logos to suit users' requirements.

This durable, long-lasting method is ideal for bespoke projects and helps save space by removing the need for legend plates and signage.

With a variety of accessories available, from earthing kits to antirotation washers, and legend plates to replacement caps and lenses, the new range of Allen-Bradley pushbuttons provides a complete safety solution, whatever the environment or application.