Issue 160 March - April 2024

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.
Temperature controlled cabinets from IP Enclosures

Whether it is outdoor low voltage cabinets exposed to the weather or indoor cabinets exposed to dust or hose-down conditions, IP Enclosures New Zealand can provide off-the-shelf or custom-built enclosures to protect electrical equipment from the adverse effects of any environmental condition.

This now includes thermal, where temperature control options can be included in cabinets to deal with excess heat.

Managing director, John Hungerford, says IP Enclosures offers a range of options to manage heat from simple ventilation fans and vents to air conditioning units.

“We are now developing thermally-controlled electrical cabinets and data racks for New Zealand applications to give you everything you need to control temperatures within enclosures,” says Hungerford. “Whatever the environment you are trying to control – hot or cold, moisture-laden or dry – we are continuing to develop new solutions to ensure optimal running conditions for sensitive electrical and data components and their longest working life.”

He says there are more enhanced cooling options available today including vent hoods, sun shields, air filters as well as heaters, internally or externally mounted heat exchangers and controllers to make it all work.

“Because we design all our cabinets, we can also add external or internal insulation and use techniques like reflective insulation and double walling to create an air gap. We can bring together a diverse range of passive and powered technologies to get the internal atmosphere and temperature right for any critical installation.

Changes needed to fix new licensing rules

Retrospective consultation is now underway to address flaws in the new registration and licensing regime that the EWRB is rolling out from September 1.

Industry organisations have stepped up and are calling for changes to the Gazette notice issued by the EWRB registrar last September 1 which created new endorsed classes of registration and changed the limits of work on existing classes.

In its 2023 annual report, the EWRB advised that electrical workers and key stakeholders had been consulted on its proposed changes to registration and licensing regime. Presiding member, Russell Keys, said in the report that the Board “received excellent feedback from our consultation; with most of the feedback being positive.”

ElectroLink asked four key stakeholder industry organisations for their response to the Gazette notice which has the effect of secondary legislation and must be complied with.

Of these four, (Master Electricians, the Electricity Engineers’ Association (EEA), and two electrical inspector organisations: Electrical Safety New Zealand (ESNZ) and New Zealand Electrical Inspectors Association (NZEIA)), only one key organisation says it was consulted prior to the changes and that was NZEIA.

President Peter Macmillan says NZEIA responded with a submission.

A lot of industry thinking coalesces in industry organisations and ESNZ president, Alec Knewstubb, says his organisation was not consulted and does not regard what occurred as being consultation with the industry. “What they did was barely suitable as a marketing exercise.”

Master Electricians’ new CEO Alexandra Vranyac-Wheeler agrees that “more robust efforts should have been undertaken, particularly considering the significant scope of the changes.”

NZEIA briefs Minister

After a decade of government fracture and bureaucratic stagnation holding back the electrical industry, is there light at the end of the tunnel?

Inspector Tony Doyle comments on an initiative by the inspectors’ group, NZEIA, to brief the incoming Minister of Energy on the failing state of government controls and a further initiative to develop NZEIA installation guidance to elevate the inspector community

In New Zealand's disjointed electrical governance, disorder reigns supreme. Quality slips, bureaucrats fumble, and decisions that shape our industry are made by those who fail to grasp its intricacies.

Enter Peter MacMillan, President of NZEIA, with a message that slices through the chaos. In an industry briefing to the new Minister of Energy, the honourable Simeon Brown, MacMillan calls for the reunification of our fractured industry governance under one Ministry of Energy, with a proposal for technical electrical experts guiding wise decisions at the governmental level in one place.

MacMillan asserts, "the leadership and accountability gap are resulting in ineffective coordination and decision-making, hindering the industry's responsiveness to emerging challenges."

He further states “our current electrical landscape resembles a convoluted maze, with no clear lines of responsibility. We are juggling WorkSafe, MBIE, the EWRB (under MBIE), New Zealand Standards, and a host of other entities, adding to the bureaucratic nightmare that leaves us all scratching our heads.”

Using AS/NZS 3017 testing to verify installations

In the March issue of ElectroLink, electrical inspector Allister McGregor provided commentary and advice on AS/NZS 3017 testing methods and alternatives. Former committee member involved in developing this standard, inspector Alan Cuthbert, responds

My attention was drawn to the article ‘Practical safety testing of electrical installations’ by Allister McGregor in the January-February 2024 issue of ElectroLink. His article contains some significant technical errors and makes some observations on the structure and the use of AS/NZS 3017 in New Zealand.

These errors must be identified as the adoption of the methods detailed, if used for verification, could provide a false indication of full compliance with the requirements of AS/NZS 3000 and the Electricity (Safety) Regulations 2010.

It has the potential that an electrical installation being certified could be left in an electrically unsafe condition if some of the recommendations he has made are used for earth fault loop verification purposes of an electrical installation.

When corrected, the article would be a helpful training aid that electrical apprentices could use in their training and for the biennial competency training of electrical workers.

AS/NZS 3000:2007 (the current cited edition of the Electrical (Safety) Regulations 2010), clause 8.3.2 provides for full compliance with AS/NZS 3000:2007 Part 2 requirements and can be used for testing verification purposes.

While AS/NZS 3017 is not cited in the Electricity (Safety) Regulations, it is called up by AS/NZS 3000:2007 Clause 8.3.1 to provide some of the common test methods required to test a low voltage installation for compliance with AS/NZS 3000.

The importance of proper programming practices

he world is getting ever more complex, by the day!

The industrial realm is not immune to this trend – virtually every aspect of what we do these days is becoming more difficult, requiring ever greater know how. This is being driven by the ever-present need for greater efficiencies in our production processes, as well as the desire for increased quality of output.

While we rely on automation to create the products we need, one area that’s often forgotten are the programs used. It’s the program code run within industrial controllers that provides all the functionality of the system.

Whether we’re creating a greater level of output, in terms of higher quality or greater diversity or increased efficiency, we’re going to need bigger and far more complicated programs to provide that functionality.

General programming principles

There are usually many different programming solutions for a given problem. The question often morphs into finding the best program that will solve the problem. While there is no straightforward answer for this, readability is now considered the most important aspect when writing a program.

Program readability is vital to its understanding, which is often given a higher priority over other desirable programming aspects, such as elegance and even overall efficiency.

The resurgence of dim-to-warm lighting+

When incandescent and halogen lamps were phased out, there was one side effect of the way these lamps worked that was initially lost with the new wave of LED products. Maybe it was the romantic ambience as we dimmed the lights that stood out the most, but there were some other key elements to the loss of the dim-to-warm effect of traditional light sources that we are only now recapturing.

Those original halogen or incandescent lamps, when dimmed, would change their colour temperature at the same time, and not only did they dim to a warmer colour, but they did it exceptionally well.

They would smoothly dim on a proportional curve to very low ranges without flicker, producing a high colour fidelity across the Colour Rendering Index. They would also have a good quantity of far red and infra-red spectrum and achieve all this without requiring any specialist control gear apart from a dimmer.

The science behind how incandescent and halogens achieve this is due to their nature as a blackbody radiator, the same as our sun. As electrons flow through the filament of an incandescent or halogen lamp, the resistance causes the filament to rise in temperature gradually, radiating energy, eventually in the visible spectrum, causing it to start visibly glowing. It starts at an amber temperature and as the temperature rises, moves through the spectrum becoming more neutral and finally heading towards a blue-white hue.

If you put your hand over an old lamp, you can physically feel the temperature difference between a dimmed lamp and one at full incandescence. It’s the same concept as how blacksmiths depend on the colour of the heated metals to gauge the temperature range they are working with.

Lighting for LPD

Lighting power density (LPD) is a very basic metric for measuring lighting efficiency within a space. It measures the amount of power (wattage) used by a luminaire, including all aspects of the luminaire, such as ballasts, control gear and other losses, per square metre of a building. In New Zealand, the Building Code, with the acceptable solution for energy efficiency H1/AS2, makes this a compulsory calculation for all communal non-residential and commercial buildings with more than 300 m² of occupied space.

As it stands, the calculation required for achieving compliance is a very blunt instrument. H1/AS2 simply refers to the current New Zealand standard, NZS 4243.2.2007 (Amendment 1), section 3.3 which is the power density limits method of Energy Efficiency – Large Buildings Part 2: Lighting. The standard had a revision, Amendment 1 which was published in April 2018, so it has made some effort to keep up with the proliferation of LED luminaires and their predominance in the marketplace, but continuing innovations around control systems and LED performance, especially their efficiency, has meant that there is a need to keep our compliance requirements relevant and to help facilitate the press ahead with stricter carbon emissions targets.

New Zealand has since introduced a complementary standard, NZS 20086:2022 Light and lighting – Energy performance of lighting in buildings, which provides a good methodology for accounting for buildings with control systems.

NZS 4243.2.2007 has sponsored access by MBIE, so this document is readily downloadable and printable for any that need to reference it from the Standards New Zealand website. The overall goal is a noble venture that ensures lighting of large buildings will utilise products that are as energy efficient as possible.