A chorus of approvals

If you've already built the product before you start to think about getting it approved, you could be in for a shock, warns E&T.

The subject of approvals usually rears its head when the product is glistening in the middle of a table during a management meeting. Add to that the fact that the final product is invariably a hastened version of its R&D predecessor. Once the engineer has got a rudimentary system working, a member of management demands: "Get it in a box ready to sell, pronto!"

It is no surprise therefore that the chances of the product passing any approvals process are stacked against it. When approvals are finally sought, there are often costly delays. Massaging the product to comply with approvals also results in something that cannot be changed to make it more cost-effective to manufacture - at least, not without revisiting the approvals process at further expense.

Take the example of an Israeli supplier, which recently lost substantial sales when it self-certified its product for an electrical safety standard without fully understanding the approvals requirements or European law.

For the target device - let us call it the Widget, and its developer Black Lasers Ltd - a critical component was being considered by its engineers, which, if used, would have been bought from the Israeli supplier in large volumes. The component in question had some useful features and benefits, however its European declaration of conformity was signed by someone who was outside of the European Economic Area, and was therefore invalid.

There were two ways out of this, the Israeli supplier could find a European distributor who would accept responsibility, or Black Lasers could accept responsibility for the supplier. The first option was ruled out by the Israelis, and, after a technical assessment of the product, it was found not to comply with their claimed standard anyway. They didn't want to relinquish any design/test data, so that was the end of that.

The point to note here is that a 'CE' mark on a product is not always a green light. If things go wrong, you and your business can end up being accountable.

Approvals history

The history of approvals - in the electrical and electronics business, at least - can be traced back to the late 19th century, when various countries began to form electrotechnical engineering bodies. Most were formed in quick succession (see opposite page). Collaborations for projects blossomed and so became a need to standardise on units of measurements and safety. These became more essential as electrical products become available commercially and businesses wanted to provide guarantees for their products:

EN60950-1 and UL60950-1 are the two big 'harmonised' approvals standards that we need to concern ourselves with here. UL60950-1 is managed by the US business Underwriters Laboratories, and EN60950-1 is a European self-certified standard. The two are variants of the International Electro-technical Commission (IEC) standard IEC60950-1. These standards relate to the safety of electronic technology equipment. They are the widely adapted de facto standards for safety, concerning themselves with a product's physical design, safety critical components, for example mains-operated parts and how the product operates both normally and under fault conditions.

For Black Lasers, the Widget needed both EN60950-1 and UL60950-1, as these two approvals bodies will open most international market doors. Other bodies do exist, but these two cover the majority of the globe.

The Widget was also designed to be incorporated into other systems. To meet this demand, the CB scheme was also engaged. CB provides limited test data that test-houses are obliged to accept when applying for country specific approvals, for example the Canadian Standards Association (CSA).

At first it may appear that approvals will be straightforward if your product has been designed with some thought. If that were true, then there would be no need for this article to be written, or for you to be reading it. It's not simple and there are plenty of traps to catch the unwary. What follows may seem excessive in parts, but the lines for safety have to be drawn somewhere. They can be seen as extreme at times, but if you know the rules of the game, you can successfully steer any project through the approvals process.

One common problem is components not complying with self-certified claims, or becoming obsolete. These can be a show-stopper. Obsolete components are the simplest problem to solve. Provided that you do add sufficient alternative critical components to the approvals project file, this issue should not feature in any role-list of mistakes-to-be-made.

Non-compliant components can be a greater problem. If your business is one of a few customers for a component from a supplier, then the supplier should oblige by making any necessary changes. If it is a widely available component, however, then the supplier will likely be reluctant to make changes.

For Black Lasers, the latter was the case. A critical component was being retailed with a CE mark, but it did not have UL approval since the supplier did not sell the part outside of the EEA. Conversely, suppliers in USA who had UL approval for the component-type did not have an EEA agent who would accept responsibility for it in Europe. Thus a version of the component with both UL and CE approval did not exist, despite an exhaustive search. The supplier in question did not want to submit a component that had CE approval to UL for UL's inspection, because the supplier saw no market return for the financial expenditure.

The solution was for Black Lasers to pay UL to certify the component only as a component of the Widget, as the device being tested for UL60950-1. However, upon investigation of the component by UL, a sub-component of the component did not carry the correct approval, so that needed testing too. Inevitably, the cost rose to an extraordinarily high level, but Black Lasers had to follow it through because of the customer's expectations.

An unexpected challenge that popped up during approvals testing of the Widget was a residual circuit breaker (RCB) that had been fitted to protect the user in the event of wiring fault. On the face of it, this is a very reasonable and rational feature of an electrical product. The part had the appropriate safety standard for an RCB, so it was designed in electrically and the metalware cut to accommodate it.

Of course, when a component with an appropriate approval is incorporated into another product, the component must comply with the standard of the product. However, in the case of the RCB, it failed when subjected to the device's required standard, which was more harsh than an RCB normally has to cope with. It did its job, but often burnt out. As a result it had to be changed and so too the metalware. More cost and a further delay, plus the Widget had to be retested once the redesign was complete.

EMC and Multiple approvals

An interesting set of circumstances arises when a product has to have multiple approvals - in particular, electrical safety and electromagnetic compliance (EMC). One aspect of EMC is that a product must limit the electrical noise it puts onto the mains. The obvious solution is to fit a mains inlet filter. The challenge here is that the mains inlet filter is classed as critical component of IEC60950-1. Somehow, both tests need to be completed together and also meet product cost requirements. This highlights the need for pre-compliance testing.

Because the Widget's approvals had been an afterthought, there was pressure from management to get the approvals completed as quickly as possible. Most test-houses have spotted this as a business opportunity, so offer 'fast-track' programmes. For a premium, this allows you to queue-jump. However, the actual testing cannot be done any quicker, so if the approvals have not been designed in, delays and extra cost will result. The high premium fee paid is then a complete of waste of money and customer promises are broken.

But let's assume the unlikely scenario that the product passed EN and UL testing first time, or an inordinate amount of money was spent to get it to pass. What next? For EN self-certification, an internal audit system needs to be put in place to keep the manufacturing process in check. This is the next elephant-trap. For UL certification, UL will regularly audit your business's manufacturing. If any serious problems are found, then your business could be faced with one of two customer-embarrassing scenarios: Either advise customers to remove the UL product label, or recall your products.

Wiring is by far the biggest banana skin after a product has cleared all of its hurdles. Awkward questions that will be asked include: "How, when and why?" Of course, it's unlikely that you will be able to pinpoint the exact answer, otherwise the mistake would not have been made, so a well maintained manufacturing process is the key.

This article has outlined only a small example of product-safety standards, but the message is that product approvals are complicated and exist for a good reason. Believing they are quick and simple has all too often proved be short-sighted and expensive, so it is worth having or hiring an experienced set of eyes to review your project before it is completed - ideally at the start of a project, or before your product is submitted for approvals testing.

Approvals bring kudos and demonstrate a level of competence, plus diligence on the part of your business. Finally, Black Lasers did eventually get EN60950-1 and UL60950-1 approvals for the Widget, but at great cost to the company and a long delay to a - by then rather irritated - end customer.

 

Stephen Clemmet is a chartered engineer and independent consultant who advises on product safety approvals and intellectual property rights and how to manage the business relationships between them. Contact him at sclemmet@btopenworld.com

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