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Cable pull switch resists corrosion

Edited by the Engineeringtalk editorial team Jun 22, 2007

Rockwell Automation's Allen-Bradley Guardmaster Lifeline 4 cable pull switch provides users with emergency stop access along exposed conveyors and around awkward machinery.

Rockwell Automation has launched a stainless steel version of its Allen-Bradley Guardmaster Lifeline 4 cable pull switch, designed for applications where hygiene and/or corrosion resistance are essential requirements.

The 316-bodied Lifeline 4 is ideal for both internal and external use, providing users with emergency stop access along exposed conveyors and around awkward machinery.

Stainless steel Lifeline 4 is one of the only investment cast stainless steel cable pull switches of its type on the market.

The new product takes the proven technology of the standard Lifeline 4 and extends it into hygiene-conscious industries, such as food and beverage, and to industries such as quarrying and mining, paper production and automotive, where corrosion can be a major problem.

The robust and cost-effective emergency stop provision delivered by the stainless steel Lifeline 4 is not only intended to help with worker safety, but also to reduce disruptions to production caused as a result of corroded cable pull switches.

Stainless steel Lifeline 4 is IP66 and IP67 rated, making it suitable for wash-downs.

The robust body is unpainted and all markings are laser etched so that they cannot flake off.

The seal between the lid and the body protrudes slightly, preventing it from acting as a food trap.

Raised pads on the switch base allow wash-down water to circulate freely behind the switch, so that product residues do not become trapped.

Complementing these external design features an operating mechanism that delivers positive, immediate latched operation in response to a definite deflection.

It also minimises nuisance tripping and the effects of thermal expansion.

The positive-mode operation is one of several major features that make the unit one of the most versatile cable-operated safety switches on the market.

In addition to its integrated cable status indicator and four sets of contacts (two normally closed and two normally open), it also includes a switch lockout and a lid-mounted, mushroom-headed EN418-consistent emergency stop button that provides an additional E-stop facility at the extreme ends of the cable span.

In common with all products in the Lifeline range, the stainless steel Lifeline 4 is easy to set up and maintain.

It can be mounted in any position using a combination of its stainless steel installation kit and the integrated cable status indicator.

When correctly installed, a pair of switches will serve as a safety grab wire, up to 75m in length.

This large span helps to reduce the number of emergency stop buttons required to offer adequate protection in applications like conveyors, while also providing a tripping facility for effecting machine shutdowns and lockouts if an operator should fall or is pushed against the cable wire.

Ideal for OEM use, the stainless steel Lifeline 4 is consistent with the requirements of EN418 "Safety of Machinery - Emergency Stop Equipment" and addresses ISOTR 12100, ISO13850, EN60947-5-5 and IEC60947-5-1 standards.

The product is also CE-marked as well as offering cULus and TUV approvals.