You may already own an insulation tester that has similar specs and features to high-end industrial insulation testers, and you might think that it’s good enough to do the work you need to do. However, if it’s not good enough you can get seriously injured, lose a lot of valuable time, perform incomplete tests and experience recurrent downtime. With that said, having the right insulation resistance tester is crucial to completing a job successfully, and more importantly, safely. But how do you know whether you have the right insulation tester for the job? Well, just like buying anything else, there are a couple of important factors to consider when shopping for one.
The first thing you need to do is make a list of all the equipment you expect to perform insulation resistance testing on. Write down all the nominal voltage ratings and the approximate number of tests that you intend on performing annually. The nominal voltage can help you determine what test voltage you need from the tester. If you’re going to be using the tester frequently, the overall quality, convenience features, and the durability of the tester become more important.
Take the Kyoritsu 3128 insulation tester, for example. It has the capability of testing insulation resistance of up to 35T ohms, with test voltages of up to 12kV. The Kyoritsu 3128 is designed for field use and it is IP64 certified. It employs a wide range of diagnostic functions, giving you the ability to test the polarisation index, dielectric absorption ratio and dielectric discharge. Of course, you also have to consider your experience level. The test instrument is only as good as your knowledge and experience in using it. The aforementioned Kyoritsu might be an overkill purchase if you can’t take advantage of its features and capabilities.
And of course, you need to consider the safety aspects of the tester. Safety is of utmost importance when troubleshooting and testing, simply because an insulation resistance tester can produce significant voltages, and they should never be connected to an energised circuit. The output of the tester can actually destroy electronic circuits. Make sure you never connect an insulation resistance tester to power supplies such as UPS systems, battery chargers, PLCs, VSDs, and any other solid-state devices. The tester you decide on should be rated for its application, and it should be suitable for the environment in which you’re going to use it.