How much light do you really need?

Paul Sowerby and Grant Mack, AllightSykes, Australia, investigate the use of a new breed in LED mine lighting technology, and explains how coal mine operators can ensure they use the right amount of light at their mines.

Safe, tough and economical lighting, capable of meeting the world’s toughest coal mining standards, is arguably now within reach, as a new breed of LED technology is launched.

However, the new techynology has brought with it came confusion over how much light is needed in various parts of a mine. Meanwhile, the spectre of asset redundancy looms large in the minds of equipment rental groups and large mobile lighting fleet operators.

Australia-based mine lighting company, AllightSykes, is now exploring LED’s role in improving operating efficiency and reducing carbon footprint. The firm is also working on a clever new way for mine operators to mitigate the risk of being left with traditional metal halide product, for which there could soon be little or no demand.

With more than 10 000 of its mobile lighting towers operating in mining and construction sites around the world, AllightSykes was a short-odds favourite to win the race to replace traditional gas-filled metal halide lighting towers with a new breed of LED alternatives.

Much of the company’s success in this regard has stemmed from an early decision to integrate a new Perkins 2 cylinder 500cc water-cooled engine, with HyperLUME® lamps from HELLA. The resulting new MS9-LED tower only requires refuelling only once every 13 days, while the tower also has integral fuel spillage containment and comes with an intelligent upgradable control system, which makes remote monitoring and control simple and efficient. It also delivers an 18 tpa carbon footprint reduction.

“Bringing such clever new technology into a range of such well-established Allight lighting towers, means all the safety and performance achievements which the LED lighting engineers have developed are wrapped up in best-practice technology, which we’ve been perfecting over 20 years,” explained Grant Mack.

“We tell ourselves that this business is all about analysing the customer’s needs and devising a solution to meet them, and extra low voltage LED light technology has been a major focus for us for some time. As the market seeks alternatives to traditional light sources, we have as usual taken all the necessary steps to ensure we remain in the driving seat as the technology emerges,” Mack added.

Previous attempts by manufacturers to give the lucrative coal mine lighting market a locally-made fully-bunded DC option came up short in terms of fuel economy and robustness. It also raised the challenge of what to do with outdated tower technology.

Asset redundancy

With the arrival of new LED technology, came huge pressure on existing owners and operators of large metal halide tower fleets to address the potentially limiting issue of what to do with their redundant assets.

To help mine operators make the switch to LED, without the trauma of asset redundancy, AllightSykes launched a Retro-fit & Upgrade lifeline.

“Having been in the mobile lighting game for over 20 years, we’ve seen new technologies come and go and understand that the mobile lighting fleets which our customers have today aren’t necessarily the ones they’ll need tomorrow,” added Grant Mack. “For many, putting too much risk before any reward just isn’t commercially viable and with the launch of our Retrofit & Upgrade solution, even those who can’t afford to adopt LED, can at least let us help them adapt to it.”

The Retro-fit & Upgrade option means rental companies and end users can change to LED even if timing and funding doesn’t allow them to dispose of their traditional metal halide units and start from scratch again.

There are four Retro-Fit & Upgrade options to make sure every budget and timescale can take advantage of the option, and the change-over can usually be funded from R&M rather than Capex budgets.

The science of mine lighting

When it comes to lighting up a work area, it’s all about watts, lumens and lux. Here follows a brief note as to how each of these relate to mobile lighting towers:

• Watts (W) are a measurement of the electrical power needed to operate each lamp.
• Lumens (Lm) are a measurement of the amount of light which each lamp or cluster of lamps is able to produce at the source (ie up in the air in the case of lamps on an extended mast).
• Lux are a measurement of the usable light which reaches your work area on the ground.

The rate at which lamps convert watts into lumens is important, and is expressed as lumens per watt (lm/W).

For example:

• A 400 W Metal Halide lamp used in most lighting towers produces 95 lm/W.
• A 100 W Incandescent bulb used for general task lighting produces 17 lm/W.
• A standard fluorescent tube used for general office ceiling lighting produces 50 lm/W.
• A 240 W lamp used in the new Allight LED lighting towers produces just under 100 lm/W.

Lux are calculated on the basis that 1000 Lm focused into one square metre lights up that square metre with an illuminance of 1000 Lux. Similarly, the same 1000 Lm spread out over, say, 10 m², produces an illuminance of only 100 Lux. Spread over 100 m², they would deliver 10 Lux, and so on

To work out whether LED will suit an area or task – and if it does so, how many LED lighting towers are needed – it is important to know how much Lux a particular task requires.

To do that, Allight’s mine lighting specialists have produced the following guidelines for various parts of a typical mining operation.

Using these guidelines can significantly improve the way a coal mining operation uses its mine lighting equipment. By taking the appropriate approach to understanding whether LEDs would be suited to an application, as well as considering how many towers might be needed, mining operators can guauge how mush light is needed in various parts of a mine. Once this is understood, companies can avoid using too much light – and this incurring additional costs – because they know how much light an operation really needs.

Written by Paul Sowerby.Edited by Sam Dodson

Read the article online at: https://www.worldcoal.com/mining/15082014/led-mine-lighting-towers-1214/