Is Your Multifunction Tester 18th Edition Ready?


The 18th Edition Wiring Regulations (BS7671:2018) come into force on 1st January 2019 having been published in July earlier this year. There have been several changes to the regulations that affect various aspects of electrical installations. However, this does not necessarily mean that wholesale change is required in terms of test equipment for electrical contractors so it is important to carefully consider before making any purchases.

Do I need an 18th Edition MFT?

There are a couple of changes in BS 7671:2018 that may prompt electricians to reconsider their toolbox. In particular, an earth resistance test may now be required in certain circumstances and type B RCDs are increasingly prevalent thanks to electric vehicle charging points. More information on these situations is given below but what's certain is that an MFT capable of performing these extra tests will save space and time as well as increasing the scope of jobs that are open to an electrician. However, whilst we always recommend keeping up to date with the latest equipment, the procedures and value recommendations for installations contained within the 18th Edition are the same as those set out in the 17th Edition, so an existing MFT is likely to meet the new requirements provided that it has been well maintained and calibrated annually.

Will my MFT need any updates?

When Amendment 3 introduced a new set of loop test values to the 17th Edition Regs in 2015, certain multifunction testers required a firmware update so that their internal value tables matched those in Amendment 3. The instruments involved offered the user a PASS/FAIL indication for loop tests and the internal values needed to be updated so that this indication remained accurate. There is no similar change in the 18th Edition so at the moment an update might not be necessary in terms of meeting the regulations, but firmware updates are always issued for a reason. This is usually to iron out any flaws in the firmware and keep it up to date in terms of operating processes so it is definitely advised to keep your tester fully updated.

Are any additional instruments needed to meet the 18th Edition?

An important new aspect of the 18th Edition Wiring Regs is in Chapter 54 which covers earthing arrangements and protective conductors. In particular, there is now a requirement for an additional earth electrode to supplement earthing facilities provided by the electricity supplier in order to prevent dangerous touch voltage if the main connection to earth is lost.

All MFTs are capable of supplementary earth testing using the loop test function but in certain circumstances, an earth resistance test may be required. Only certain MFTs have this capability e.g. Kewtech KT65DL, Megger MFT1741 and Metrel MI3125BT, so those with a more basic model may wish to hire one of our earth testers from £90+VAT per week or purchase their own model from our earth tester catalogue.

What about RCD testing?

Whilst all MFTs are capable of testing A-type RCDs, B-type RCD testing is another matter as these RCDs protect users from shocks from DC current and have therefore been relatively rare until a few years ago when electric vehicle charging points were rolled out. Only around half of the MFTs on the market can test this type of RCD so the user may wish to upgrade if they hope to branch out into EV charging points as demand increases. Suitable models include the Dilog DL9118 and Metrel MI3152 and we even stock the Metrel A1532 EVSE Adaptor which is specifically designed for this application.

18th Edition Ready?

Although new equipment is not necessary to comply with the 18th Edition, all MFTs must be correctly maintained and calibrated annually to ensure accuracy and reliability as well as spotting developing faults early. We offer a speedy, professional calibration service at our state-of-the-art calibration laboratory.

Moreover, we would always encourage electricians to keep up to date with the latest equipment because of the many benefits of more sophisticated testers. For those looking to upgrade their equipment, we offer a wide range of MFTs from basic models to industry-leading instruments with a great range of free gifts and kit options.