Enclosures
Why your next industrial electronic enclosures could be plastic
By Robert Cox, marketing director, OKW ENCLOSURES LTD I
ndustry 4.0, IIoT and digitalisation are not just revolutionising factories – they are also transforming the way that electronics are housed in today’s modern technical facilities.
Before Industry 4.0, diecast aluminium and stainless steel were the obvious materials for protecting industrial electronics. Their toughness and ingress protection made them the prime choice – but now plastic enclosures are finding ever greater favour on the factory floor. True, there has always been a place for plastic enclosures in industry – especially glass-reinforced polyester (GRP) which offers excellent protection in environments with a high risk of chemical hazards. But the feeling was that aluminium and steel enclosures always ruled the roost. However, now there is a noticeable change. Aluminium and steel enclosures remain important with specialist enclosure manufacturers continuing to unveil new models designed to offer ever-greater protection. But now these metal enclosures are sharing the honours with increasingly advanced thermoplastic housings. It is now possible to mount your electronics in extremely tough plastic enclosures that offer an IK impact rating comparable with stainless steel enclosures – but at a significantly lower price point. That in itself is quite a coup but the benefits of plastic enclosures don’t stop there. There are now plastic enclosures that offer not just the durability but also the ingress protection and advanced technical features of diecast aluminium enclosures. And those features should not be underestimated; simple design details can play a crucial role in keeping your circuitry safe.
So, what should industrial electronics 44 July/August 2023
by the material and the seal are of little consequence if the electronics are compromised while the enclosure is being installed.
Industrial environments are by their very nature challenging. Especially the great outdoors. Windblown rain can damage electronics if the enclosure has to be opened in order to fit it in place. So good industrial electronic enclosures are designed to be fitted ‘lid closed’; there are separate screw channels for the lid screws and the mounting screws.
OKW’s MINI-DATA-BOX is designed for compact ‘go-anywhere’ industrial electronics
designers and specifiers look for? What separates the plastic enclosures aimed at offices from those that can survive the punishment of life in a factory? It starts with the plastic. Acrylonitrile butadiene styrene (ABS) used to be the go-to thermoplastic polymer for enclosures because it is strong, cost-effective and easy to machine.
But in recent years, ABS has been superseded by UV-stable Acrylonitrile styrene acrylate (aka acrylic styrene acrylonitrile) which provides far greater protection against the damaging effect of the Sun’s rays.
Even more popular are blends which combine ASA with polycarbonate (PC) for added strength. Polycarbonate is used in the manufacture of riot shields, bulletproof glass and CDs so its robustness is
Components in Electronics
undeniable. Blends such as ASA+PC-FR (UL 94 V-0) are also more flame retardant than ABS (UL 94 HB).
And yet ABS remains an important plastic. In a PC+ABS-FR (UL 94 V-0) blend, it can provide impact protection of IK 08 – making it more resilient than some stainless steel enclosures.
Material strength is only half the story though – ingress protection is crucial. Non-industrial plastic enclosures tend to offer little defence against dust and water. Some provide IP 54 or IP 65 protection but industrial electronic enclosures need something more: IP 66 (for temporary flooding, such as rough seas), IP 67 (for temporary immersion in shallow water) or IP 69K (for high-pressure, high-temperature spraydowns at close range). And yet all the protection provided
Lid retaining straps and captive screws are very useful if enclosures are to be installed at height. It’s all too easy to drop a lid or screw if you’re struggling to install a unit in high winds or other inclement weather. And if regular inspections are needed, then it’s worth specifying an enclosure with integrated lid hinges. The enclosures should also have a recessed lid to accommodate a membrane keypad or product label. There should be plenty of space on the sides for cable glands and other connectors. Look for side recesses if you need to afford those interfaces some extra protection. Inside, the enclosures should have fastening pillars for PCBs, mounting plates and DIN rails. Accessories are an important consideration too. Think about extras such as security plugs (for use with anti-tampering lead tags) or pressure equalisation elements that protect sensitive electronics during changing atmospheric conditions and sudden drops in temperature.
Electronic enclosures manufacturer OKW’s new SOLID-BOX (IP 66, IP 67) exemplifies the new breed of plastic housings for industrial electronics. It has
www.cieonline.co.uk.uk
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66
