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In-house or outsource? The decision’s yours01 May 2008Whether you build your panels and enclosures in-house and keep a tight control over quality and inventory, or decide to get a specialist to do the job for you, there are various things you need to consider. Les Hunt touches on some of the key issuesIt’s a fairly straightforward question: do you buy in the metal and presses (or, indeed, plastics and injection moulding machines) and form your own enclosures, or do you go outside your business and buy them from those who make this a speciality, thus saving you all the bother? Well, I suppose this question poses one or two dilemmas: is it worth investing in the necessary manpower and machines just to say you are in control of quality and inventory, or are the economics so finely balanced that you could, indeed, go in either direction?
With any panel building operation, it is perhaps not surprising to see various aspects of the manufacturing being ‘outsourced’, particularly as the alternative will involve a great deal of capital investment. Now, more than ever, this ‘metal-bashing’ activity goes eastwards into Europe or further afield where production costs remain attractive to western manufacturers.
Of course, there are exceptions. The Honeywell Fire Systems subsidiaries, Notifier and Morley-IAS are illustrative of companies that have decided – for very sound reasons – to keep their panel building operations in-house. They have a huge portfolio of products and enviable reputations to maintain, and controlling the quality of their manufacturing operations is paramount. The offshore option simply doesn’t bear scrutiny.
But even these companies will consider an external supplier if the economics dictate such a move. The panels that Honeywell’s subsidiaries build are generally small, wall-mounting units housing electronics, control devices and displays in many different configurations. However, a specialist part of the business calling for larger, free-standing enclosures for 19in rack mounting, is satisfied by an external supplier – in this case Rittal and its award-winning and highly flexible TS8 product. And that word, ‘flexible’ probably says it all.
In the past, system builders in favour of the outsourcing approach would have been happy enough to purchase a standard enclosure from one supplier, a cooling system from another and the essential cabinet hardware components like power distribution buses from yet another supplier, and be prepared to put them all together in-house. That works fine until you encounter assembly problems that might set back your production schedule.
Enclosure manufacturers such as Rittal identified these problems early on and have designed ‘standard’ enclosures that offer extraordinary internal mounting flexibility. Moreover, these enclosures provide frames with two sets of punched levels - an outer and an inner - that enable more than one component or bracket to be fitted at any one point. This, plus the symmetry of the frame, enables the same brackets and components to be fitted in both the width and the depth of the enclosure. Fitting shelves, door switches and similar equipment – even the re-positioning of a mounting plate – become quick and simple tasks.
Doors, rear panels and side walls are manufactured with common dimensions for any given enclosure size. A side panel can thus be exchanged for a door, or a rear panel can become a door without any major engineering work. The same mounting system can be used for the installation of enclosure climate management equipment, such as heaters, cooling fan trays, anti-condensation units and the like.
And when it comes to power distribution, Rittal can supply modular busbar systems that use the punched hole system in the frame for attaching the necessary mounting brackets and insulators. These systems work on the principle of a standard bar spacing for a range of power levels. The tops of the bars are always a standard height from the back plate, with adjustment for different bar sizes being achieved using inserts between the busbar supports. With this level of standardisation, power distribution design and build becomes a much less onerous task.
In the present economic climate, you have the edge on your competition if you can get new products to market quickly and at minimal cost. Similarly, you will possibly improve your position in a tender list if you can demonstrate to a potential client your ability to respond just as quickly and cost effectively to a panel construction contract.
Most enclosure manufacturers offer variants of standard ranges to cope with those awkward problems associated with the fitting of unusually sized components or special requirements like EMC compliance and IP rating. It is tempting to take advantage of this and complete the remaining customisation in-house. But, as has already been outlined in this article, this is likely to involve the purchase of special machines and the appointment of crafts people to undertake the work. The alternative is to hand over the whole job to your enclosure supplier.
If your requirements can be met by small plastic enclosures, for example, manufacturers like Spelsberg and Fibox may be able to help. They are geared up for this activity, having made the investments in CNC equipment and plastic injection moulding machines, and they are able to react very quickly to your needs. Spelsberg, for example, says it can turn around a customised polystyrene or polycarbonate prototype enclosure in as little as 48 hours. Customisation is the next step, a process that could involve anything from milling, drilling and engraving, to special cable entries, connectors, PCB rails and even screen printed logos and branding.
Spelsberg cites a high-volume project it carried out for a large telecoms provider, which commissioned junction boxes for its outdoor power supplies, ready fitted with busbar, circuit breakers and cable glands. Through the savings made in terms of a reduced supplier base, administration, logistics and production time, this single customisation project reduced the overall cost of the power supply circuit protection element by around half a million pounds.
Whether you build your panels and enclosures in-house or outsource to specialists depends on many factors, some of which have been touched upon here. There are economies of scale to weigh up, as well as operational considerations; in the end, it’s down to you. Contact Details and Archive...Related Articles...Most Viewed Articles... |
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