The need for safety in testing

By
Thursday, 14 August, 2003

Specifiers and purchasers of portable test instruments are, in many cases, giving insufficient consideration to safety, according to test and measurement expert, Megger. The company is finding that, all too often, little consideration is given to operator safety, or to the suitability of the instrument for the application in which it will be used, despite the fact that such benefits are available for no cost premium.

"There is a world of difference in measuring a high voltage in the back of a television set, and measuring the same voltage in a factory distribution board," says Graham Heritage, of Megger. "In the first instance, if something goes wrong, the result may be a few sparks and a damaged component or two. In the second instance, the result could easily be an explosion resulting in serious injury or worse."

To help test instrument users avoid these problems, Megger provides clear information for all of its instruments, regarding the categories of application, as defined in IEC61010-1 1995, for which they are appropriate. To further enhance operator safety when using its instruments, the company has also developed the unique Intelligent Safety System which is featured in all of its latest continuity and insulation testers.

Designed to ensure optimal protection for instrument users under all conditions, this system not only provides live-circuit protection, but also incorporates a safe-contact detector, an auto discharge system, and a test-lockout feature. Irrespective of the range selected, live-circuit protection automatically switches the instrument to the voltage range if a voltage of more than 25 V is detected across the probes. The voltage present is shown on the display, and the user is alerted by a series of warning beeps.

The Intelligent Safety System supplements these individual safety features with an overall test lockout function which, when external voltages are encountered, prevents tests from being performed if they would yield misleading results, or if the conditions are dangerous.