Accelerometers Obtain Hazardous-Area Certification

Wilcoxon Research has announced an additional intrinsically safe certification in accordance with IECEx requirements for six general-purpose accelerometers. The six accelerometers were approved for use in Class I Zone 0 hazardous areas. Tom Smith, vice-president of sales and marketing, said: 'These vibration sensors were previously approved as intrinsically safe by certifying agencies recognised in the US, Canada and Europe.

'Condition monitoring is growing in popularity across the world and the IECEx certification will help us better serve customers in other regions,' he added. Six general-purpose accelerometers, with a sensitivity of 100mV/g and a +5 per cent sensitivity tolerance, were certified as intrinsically safe in accordance with the requirements of the IECEx standards. The standard top-exit model is the 786A-IS.

The standard side-exit model is the 787A-IS, which is also available with a metric M8 mounting stud (model 787A-M8-IS). The 780A-IS is a compact sensor. The integral cable model is the 786F-IS. The 786T-IS is a dual-output model that senses both vibration and temperature. The six general-purpose accelerometers are suitable for the industrial machinery health monitoring of rotating equipment such as motors, pumps, fans, compressors, vibrating conveyors, chillers, gearboxes, reciprocating compressors, blowers, cooling towers, mixers, turbines and centrifuges.

These types of machinery are typically found in hazardous-area locations common to industries such as petrochemical, oil and gas, chemical processing, pharmaceuticals, food and beverage, pulp and paper, wastewater treatment, nuclear power and power generation. The IECEx standards are recognised by most industrialised countries, including Australia, Brazil, Canada, China, Croatia, the Czech Republic, Denmark, Finland, France, Germany, Hungary, India, Italy, Japan, Korea, Malaysia, the Netherlands, New Zealand, Norway, Poland, the Republic of Serbia, Romania, Russia, Singapore, Slovenia, South Africa, Sweden, Switzerland, Turkey, the UK and the US.

The International Electrotechnical Commission (IEC) publishes the IECEx scheme, a set of standards that specifies requirements for both hazardous-area electrical equipment and requirements for the quality system of manufacturers of hazardous-area electrical equipment.

Certification organisations perform the testing and qualifications required by the IECEx scheme. Wilcoxon sensors were tested to the IEC requirements by Kema and have been certified by Sira to meet the quality system requirements of the IECEx scheme. The company also offers other accelerometers and 4-20mA sensors certified to be intrinsically safe, explosion proof and approved for use in Class I Division 2 (Zone 2) environments.

Laser Lines Marks Code On Tiny Area Of Oil Seal

Laser Lines has recently marked a 10-character code on the outer ring of a customer's oil seal. At the 10.6 micron CO2 wavelength, rubber materials mark very well, but the unusual aspect of this mark was the size of the mark area on the outer ring: it measured only 1.25mm (0.049in) high. The marking set-up consisted of a Synrad laser, FH Flyer marking head and the Synrad Winmark Pro laser-marking software.

The FH Flyer head was equipped with an 80mm focusing lens that provides a 116-micron spot with a 0.8mm depth of field. To create legible text marks, the rule of thumb is that character height should be a minimum of seven-to-ten times the focused spot size. For this application, the character code was 1mm high, which is on the low-end of the range for an 80mm lens. To create this mark, the 'Simple' stroke font was selected, a text height of 1mm was set, 0.15mm of extra character spacing was added, and a text radius of 54mm was entered to match the curvature of the seal.

On the marking tab, power was set with a duty-cycle percentage equal to 10W; a velocity of 1016 millimetres per second was added, and the mark-passes property was set to four. By making four complete passes, the rubber surface is vaporised slowly in small increments, resulting in a cleaner, more distinct mark. The characters are well-formed; the engraved 1mm-high text can be easily read without magnifying aids. This small 10-character code, with four mark passes, was created in a cycle time of only 0.13 seconds per part.