The Megger CM500 Tester Is History!
- Published: Monday, 06 June 2016 10:03
Don’t buy a Megger CM500 multifunction installation tester! It’s a versatile and dependable instrument that’s definitely built to last, but there’s a problem – it went out of production more than a decade ago.
Nevertheless, as you would expect with a product from a company as innovative as Megger, the CM500 offered functionality that was way ahead of its time, so it's a fair bet that more than a few are still in use today.
One that certainly is, belongs to Rob Appleby, the proprietor of Appleby’s Electrical Services in Tyne and Wear. His CM500 has been used every working day for more than a decade to test a wide variety of domestic, commercial and industrial installations – and it’s still functioning as well as it did on the day it was purchased.
“When I set up my business in 2004, I made the decision that I would buy the best tools and equipment,” said Rob, “and for me that definitely meant buying a Megger test set; I’d used Megger equipment since I was an apprentice and I knew I could rely on it for quality, performance and durability. The CM500 was particularly attractive because it had all of the functions I needed in a single instrument. Remember that in those days, it was common to use separate instruments for each type of test, but I’ve always felt that was far less convenient.”
“The CM500 certainly wasn’t the cheapest tester I could have bought,” he continued, “but it was worth the extra. In fact, it’s turned out to be one of the wisest business investments I’ve ever made, and it’s paid for itself many times over. It’s never failed me and it’s never needed any repairs, although I do, of course, ensure that it’s calibrated regularly.”
While Rob is still very happy with his CM500, he admits that it might soon be time to retire it from regular use. This is not because of any problems with the long-lived instrument, but because developments since 2004 have allowed many invaluable extra features to be added to Megger’s latest MFT1700 range.
In particular, Rob knows that automatic RCD testing would save him a lot of time, and that a choice of loop test methods, including two-wire and three-wire non-trip testing, would be very convenient. Automatic Zmax determination, where the instrument remembers the highest Zs value for the installation, is another feature that interests Rob.
“I don’t even have to think about where to go for my next tester,” said Rob, “it simply has to be a Megger. The only problem I have is trying to decide which model to buy – they’re all very tempting, but maybe a MFT1721 or MFT1731 would be a good choice for me, as both of these support working on three-phase systems, which would be a big help for my industrial jobs. Even when I have my new tester, however, I’ll be keeping my CM500 – it’s still too valuable for me to let it go!”