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An introduction to sound insulation testing

A curt introduction to sound insulation testing to comply with Part E of the Building Regulations. We demonstrate the test procedure and get across ...

why insulation testers operate on DC and not on AC?

Mar 29, 2008 by rahu | Posted in Engineering

If you use AC then the insulation acts like the insulator in a capacitor and some ongoing will flow. Using DC there is no capacitive effect so no current flows unless there is a fault.

How does the automatic discharge function work on a 5kV insulation tester (in laymans terms)?

Oct 30, 2007 by Andy | Posted in Engineering

I differentiate there are internal discharge resistors but I don't know how they function.
This 5kv Megger is a stand alone unit and is not connected to globe.

The custody just drains through high value resistors.e.g .if there was 5kv across a capacitor and you placed the resistors across it the charge would at the end of the day equalise i.e. zero.

Is there special MEGGER (Insulation tester) available for hazardous and intrinsically safe areas?

Nov 28, 2008 by Viky | Posted in Engineering

Oridnary Meggers are not certified to be adapted to in Hazardous areas in Process Industries.

Look in the rules book in article 500 about explosion proof locations it pretty well explains the boundaries that any non-paddywhack proof device can exist in. In the case of a megger the entire test is a stretch of the border on what or what is not intrinsically out of harm's way ..If there is such a device the arc produced (outside the generated internals) would have to take place between two seals . IN the case of an underground feeder where grand voltage and amperage was expected a temporary stay of area restriction might be acceptable ..Done with proper dissovled gas sniffers and with authorized personel . In most cases the collapse voltage of the wiring has been testified to by the installer .Unless you are already at ground potential on one of the conductors and your voltage is low <600vac you are probably good to go. There is a lot of space between probably and for sure though. Unfortunatly extension of the megger to an outside spot violates the code as well as any current carrying conductor must be sealed on the entering side if in conduit. Since the megger produces a higher voltage than the class of insulation an arc is produced. That being the case that arc is in violation of the code as well. I really don't see anyway to overcome 1. the lack of equipment 2. the violations of code 3.the probable value of the test ....and like I mentioned before if your at ground fault allready a simple High Imped. digital ohmeter is all you need...Wish i could help you more..From the E