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The next evolution of Ring Main Unit switches designed for New Zealand

by A D Riley, on Jun 25, 2020 2:52:39 PM

Ultra-low maintenance, Outdoor Ready and environmentally friendly

For many years, Arthur D. Riley's Power Distribution and Control division has supplied power products to major utilities and industry throughout New Zealand. One of our more unique products developed specifically for NZ is our Ring Main Unit (RMU) - HALO. It's 11kV switchgear, and there are many of them located on roadsides and substations throughout New Zealand.

Power utilities use them to isolate power in certain neighbourhood areas - it could be because:

  • A vehicle has hit a power pole

  • There has been power fault

  • Power lines have come down

  • Network maintenance

When these events happen, our power utility customers use the HALO device to isolate power in the affected area, instead of it running continuously and potentially causing more harm to individuals or damage to property.

What makes the ADR HALO unit stand out amongst its peers is its environmentally friendly configuration. Historically, units like these operated with gas, but the HALO utilises new technology. Not requiring gas reduces any negative impact upon the environment which is increasingly being brought into question.

This is a feature that is rare in these kinds of units; the technology is not yet widely used in the marketplace. As companies and utilities begin to focus on their environmental footprint, demand for units like the HALO is increasing. Within New Zealand, we’ve seen increasing demand to reduce our reliance on gas, and the ADR HALO is one of few options in the market that meet this environmental remit.

However, the use of this new technology means that the HALO unit is not as cost-effective as the gas options at purchase, but investment in them brings other benefits to off-set the initial cost difference. Being gas-free, they're ultra-low maintenance and don't require regular inspections like gas units. What near-zero maintenance means is:

  • No SF6 audits

  • No SF6 end of life handling issues

  • Reduced health and safety issues

  • Reduced cost of ownership over the life of the equipment

The HALO initial investment is paid off over their 30 year lifespan. They're also highly durable. Being very compact units manufactured from stainless steel, they are built to weather New Zealand conditions better than their elect steel counterparts, meaning:

  • No corrosion issues

  • IP55 without additional enclosures needing to be fitted

The HALO unit is modular, meaning they can be easily configured to any customer's specific needs. ADR can create a bespoke HALO solution that is tailored for individual requirements. The compact design also means intuitive operation providing increased operator safety.They carry the highest public safety rating in terms of ring main unit safety classifications, classified as B-FLR.

In terms of automation the HALO:

  • Can be added onsite after installation

  • Has multifunction protection relays available with SCADA compatibility

  • Is flexible and configurable

Historically, the type of switchgear that has been in use in New Zealand for decades has been effective, but environmental challenges and conditions required new technology. ADR have harnessed that technology and HALO is the result - the next evolution in ring main unit switches.

If you'd like to find out more about the HALO RMU, drop us a line and we'll get a discussion started.