Index to articles on this site added in June 2009

Don’t try and second guess how I purchase things

Original article date: July 2000
The other day, I installed a telephone extension socket. The kit from B&Q included the cable and clips, the new socket, and all the instructions for tapping into the existing BT socket.
Wiring into the new socket was an annoyingly fiddly job, and I was not looking forward to something similar at [...]

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Permanent magnet motors eliminate gears

Original article date: May 2000
PM-driven dynamometers to 300kWAndy Gardner of Meiden Europe explains why permanent magnets keep the heat down in dynamometers – and why it’s a good thing.
Permanent magnet motors are now being used by Meidensha Corporation for a new range of dynamometers with continuous ratings up to 300kW that eliminates gears, achieves ultra-low [...]

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Gears, Brakes and Clutches

Original article date: January 1998
Why hasn’t planetary gearing been adopted more in the UK? It’s also normally possile to replace an existing gearbox with a planetary equivalent. Here’s the case in favour of this type of motion!
As buyers of foreign machinery will notice, planetary gearing has a far higher market penetration elsewhere in the world, [...]

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Rapid prototyping in miniature

Original article date: April 1999
In only 3 years from the first stereolithography product from 3D Systems the company has now launched its first office-sized machine no larger than an office photocopier.
Developed by 3D Systems in Valencia California the Actua 2100 is a 3D concept modeller no larger than a standard office photocopier. It allows designers [...]

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Barcodes, Linux and stuff

Original article date: May 1999
A couple of issues ago I talked about streamlining the purchasing process by creating “plug and play suppliers”. I received some correspondence from readers pointing out that every day, goods-in departments and accounts departments key in large amounts of data (eg delivery note numbers, order numbers, invoice numbers) when these could [...]

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I cannot view a standard via the web!

Original article date: June 2000
It has always infuriated me that I cannot view a standard via the web to see if it is the one I want to buy. BSI clearly thinks that such a resource would be abused, and that even it it charged a small fee for an online read – say 50p [...]

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New starting method for induction motors

Original article date: June 1999
Emotron launched the MSF range of soft starters to coincide with the industry fair at Hanover. A new starting method means that mechanical and electrical stresses can be significantly reduced
Soft starters are used for gentle starting and stopping of induction motors. Pumps compressors mills fans and saws are applications where they [...]

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Understanding fatigue-rated transducers

Original article date: November 1997
The term fatigue, when applied to a load cell or torque sensor, is one of the least understood terms in the transducer industry, says Paul Armstrong of Amber Instruments.
Typically, sensors that are manufactured for general purpose applications have been “de-rated” to one-half the normal output and then called “fatigue rated”. Since [...]

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Is it just stress – or is it HARASSment?

This article was originally written in the period 1995-2000
Gabor Martell, Managing Director of Montford Instruments, explains the principle of HARASS testing of products incorporating electronics.

Thermal stress screening is an established way of exposing hidden faults which do not show up during normal testing. This happens because sub-standard components and connections often function correctly at first [...]

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Falling over a lot in the snow

Original article date: March 1998
I’ve just come back from skiing. Well OK, snowboarding (that explains the pleasant aroma ­ Ed). Well, OK, falling over a lot in the snow. And the Winter Olympics are all over the TV, so it seems like an appropriate topic for a discussion.
Let’s take a (UK pounds)15 ski pass. For [...]

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