STEPs to greater understanding
November 1st 2004

A complete lifecycle safety engineering service has been introduced by Siemens Automation and Drives.

Known as STEP (Safety Technology and Engineering Partnership), it covers risk assessment, validation, continued maintenance and system revalidation.

Ian Clay, editor of IP&E, attended the launch

As safety systems become increasingly complex, components more closely interlinked and legislation more demanding, there is increasing pressure on manufacturers and users to understand which standards affect them and how to apply them appropriately.

STEP is a response to the need for greater understanding of both regulations and standards in the marketplace. Its launch follows a recent HSE survey entitled ‘Out of Control’, that revealed that 60% of the accidents analysed were caused by incorrect design or implementation of a safety system.

This means that the systems were fundamentally flawed even before the equipment was put into service. The remaining 40% of accidents were caused by poor installation, incorrect maintenance and uncontrolled modifications. None of the accidents was a result of product failure.

Siemens is concerned that software engineers, when asked to solve a production problem will not consider safety requirements in their solution. Indeed, Rob Sharrock, business development manager - safety integrated, says A majority of software engineers have no understanding of what the safety requirements are.

Distributors

As part of STEP, Siemens has asked its distributors to commit, where possible, to increasing their knowledge and advice capabilities in the field of safety. Where this has not been possible, the company has sourced a third party provider (Functional Safety Engineering a specialist safety company) to provide these services direct to the distributor. Unsurprisingly, one motivating factor in the introduction of this new service is a rise in litigation. As Rob Sharrock states If the product does not do what the

user thinks it will do, who is to blame? Because of this Siemens now wants its distributors to provide much more information.

Customers still deal with their normal sales channel but now have the back up of a company (Functional Safety Engineering) that has 30 years experience in the field of machinery safety.

Integrators

Siemens is also putting its Solutions Partners through the same process. Each company will be assessed on its ability to supply a complete safety solution.

Assessment is based on establishing and quantifying the competency levels of each integrator, a process that can be monitored as safety standards develop. The STEP programme means that whether an end user requires a stand alone safety relay or a complex failsafe PLC, Siemens and its partners can provide, according to Rob Sharrocks, People that can give real help and real information.

As well as launching STEP, Siemens has now released an enhanced version of its ASi safety monitor and software. Following the launch of ASi Safe in 2001 Paul Hingley, product manager, communications and safety products, makes the claim that ASi is Now a de-facto standard with 10 million nodes being announced at Hannover 2004.

ASi safe refers to the integration of standard control products and safety control products and this latest advance in safety monitor technology will deliver enhanced flexibility for the end user while still maintaining safety integrity to EN954-1 and IEC 61508.

Available in basic or enhanced versions, the ASi Safe Monitors give users the option of one or two dial channels of operation.

The software is common for both variants and is selected using a matrix contained in the software’s opening tabs. The new safety monitor offers a number of features that are intended to make the change to ASi Safe even easier. The enhanced version has a safe time function (switch on and switch off delay functions); declaration of ‘debouncing contact’ for guard door safety switch; safety guard with lock operation; a function button; declaration of dummy device (NOP); and new functional components (flip-flop, pulse if positive edge etc.) The basic version has also been upgraded.

The new features allow a competent engineer to integrate the safety functions into not only simplistic control circuits but also control circuits involving complex mechanical control functions, such as mechanical presses and high speed rotary machines requiring maintenance access. A yellow front panel has also been introduced to the device. This is now a common point of recognition for engineers using this range of safety control devices. The front panel can be used to identify all Siemens IP20 DIN rail mounted devices.

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