Issue 122 September - October 2017

Please note: The issue content below is just a summary of the articles in the printed magazine.
The articles are not available on-line. Please refer to the printed magazine for the complete article.
Measure voltage without test leads

If you are looking for an entry level tool to test voltage, current and continuity safely, the new Fluke T6 electrical testers are in a field of their own. Designed around what Fluke calls FieldSense technology, the T6 senses and measures voltage up to 1000 V AC through its open jaw and without test lead contact to live parts.

Launching in September, the T6 is a technology advance on the Fluke T5 and comes in two models: the T6-600 and the higher performing T6-1000.

The T6-1000 has the unique advantage of simultaneously displaying voltage and current, says Fluke’s Australian product application engineer, David Farquharson.

“The T6-600 allows you to check voltage and current by switching from one to the other, but the advanced T6-1000 allows you to measure voltage and current at the same time without having to ‘probe’ twice.

Cable replacement underway

The hunt is now on to identify sites where substandard building wiring cable has been installed around Auckland. The electrical regulator is calling for anyone who knows where cable supplied by contractor Lyon Electrical has been installed to contact Energy Safety so that the safety of the premises can be restored through the removal and replacement of the non-compliant TPS.

Lyon Electrical, or an associated company is believed to have imported this cable and installed it on a number of projects in Auckland over the past year or two. Lyon Electrical Ltd is now in liquidation.

Energy Safety’s principal technical advisor, Peter Morfee, says Energy Safety is working with the liquidator to identify the work carried out by this contracting company.

While nowhere near the scale of the 22,000-home rollout of defective Infinity-branded cable in Australia, the impact on the primarily apartment developments, their developers and owners in Auckland is no less severe. The cable failure has provided a wake-up call to the electrical and construction industries, and steps are being taken by the regulator to raise the risk category for building wiring cable to minimise the risk of it happening again.

Time to restore airport and aviation standard

It has now been ten years since the then government hung electrical engineers, avionics engineers, electricians and inspectors out to dry by allowing the Standards NZ Council to unlawfully revoke the only standard available to wire airport and aviation installations for 115 and 208 volt, 400 hertz supply.

The withdrawal of this standard removed the only standardised means available to demonstrate the compliance of aviation supply distribution systems to ground support electrical equipment for large aircraft in hangars and workshops, as well as to aircraft on the tarmac. This standard also provided a means of demonstrating the safety of aviation specialised equipment.

Since then it has been up to engineers to design electrical installations relying on their own judgement rather than world’s best and standardised practice. This has resulted in non-standard electrical installations that, at best, might be safe but are likely to be delivering power converted from MEN to TNC with no consistency of approach for service and maintenance crews to deal with in major airports up and down the country.

However, this might change with the restructured Standards New Zealand now thinking about re-instating Section 6 of NZS 6114 which its predecessor organisation withdrew in contravention of the procedures prescribed in the Standards Act. (See ElectroLink, April 2008, page 7, ‘Death of a standard’)

No uptake for new downlight standard

As domestic downlights designed to the new joint edition of the standard for domestic downlights creep onto the market, questions are being asked as to whether they are okay to install. The short answer is no.

There is another answer that involves lying in a crumpled heap on the pavement and imagining Dirty Harry has a Smith & Wesson Model 29 revolver pointed at your forehead and asking you if you feel lucky. If you do feel lucky you can go ahead and install these Australian-style downlights, but you will lose the protection of the law and leave yourself open to prosecution.

The long answer was published in ElectroLink last year (May 2016, page 61, ‘Downlight standard upgrade on hold’). This article confirmed that the New Zealand-only provisions in the upgrading of AS/NZS 60598.2.2:2001, including Amendment A for recessed luminaires remained in force, irrespective of the publication in February 2016 of a new joint version of this standard that brought Australia into greater alignment with the New Zealand-designed solution.

The status of the 2016 update to AS/NZS 60598.2.2 remains unchanged today. It sits in the standards infrastructure, but is not cited in the Electricity Regulations (Schedule 4) as an applicable standard for determining the safety of domestic recessed light fittings. This means that anyone wanting to ensure the safety and compliance of such downlights under the law still has to utilise the 2001 version along with Amendment A which established the current testing requirements and IC-F, IC, CA80 and CA135 markings in 2011.

Become the local lighting expert – Part III outdoor lighting

f you’re an electrical contractor doing residential work, this series of articles is designed to help you become the local lighting expert and grow your business as a result. Let’s look at how you can bring your customers’ gardens to life after dark.

Good exterior lighting can –

  • highlight architectural features of the house,
  • make the property safer and more useable at night, and
  • add depth and interest to the garden and outdoor living areas.

Your customer may have put time and money into a garden that they can only see during daylight. Their investment is wasted during the night hours if the garden is invisible. With a few outdoor light fittings, carefully placed, the garden will be visible, welcoming and interesting after dark.

The glaring issue – what is glare, and why does it matter?

If you are carrying out an activity in a comfortable amount of light, but there is a significantly brighter light source that is intruding and causing a problem, then that is glare.

A common example is trying to do screen-based work in a room where the desk faces a sunny window. If unwanted light makes it physically more difficult to see your screen or task, that’s called disability glare.

The other type of glare is called discomfort glare. It doesn’t directly affect your vision but it can make you uncomfortable, unfocused or give you a headache. This is the glare from prolonged exposure to overly-bright overhead lighting or some other light source outside your immediate visual task area. You might have discomfort glare at the cinema if there is a low-level step light shining at the edge of your vision, or when working in an office where there is a bright ceiling fitting just beyond your screen.

Both types of glare can be tiring and unproductive and can affect people’s health. Disability glare can also cause falls and accidents. For that reason, New Zealand’s lighting standards have a lot to say about glare. Section 8 of AS/NZS 1680.1.2006 deals with glare and related effects and includes advice for reducing glare.