In the previous edition, Dale West looked at the ten most challenging issues with high voltage. In this edition, he’ll discuss the forgotten control measures in addressing those issues.

Switching high voltage (HV) equipment is a small part of the responsibility of an electrician, and yet it’s a vital skill. Due to the limited time spent doing it, and the exponential level of responsibility, we try to compensate it with technology.

Unfortunately, as technology progresses, cognitive development regresses. We saw this with the calculator, as an example. When I was a lad, you weren’t allowed to use a calculator at school but as I started to use it more, I noticed that I couldn’t be bothered doing simple calculations in my head and now, instead of thinking for a moment, we instinctively reach for the calculator.

I believe artificial intelligence (AI) is the latest invasion of cognitive development. It reduces our presence in the process of development to the level of uselessness, bankrupting our ability to think, reason and create.

AI is already on the cards for writing isolation procedures. Eventually, we will be incapable of determining if the AI-generated solution is acceptable.

I see this already in pre-written switching programs. The team doesn’t retain the skill to effectively check the accuracy of the program against the developing hazards in the field and update the program.

Most people are either scared of HV or show a healthy respect for it. This makes it hard to understand why there is so much complacency around HV.

Current issues with HV

• We test for dead in LV, but not HV.
• We opt for the cheapest services on the market.
• We allow operators to not follow the site procedures.
• We want less and less training while expecting safety and processes to improve.
• We don’t have the time or expertise to train new people who join the HV team.
• We ask operators to switch HV without the assistance of a second HV specialist to double-check the process and equipment and keep an eye out for hidden hazards.
• Without fully understanding HV, we are accountable for who we appoint as operators.
• We are held accountable for the above shortfalls in the event of an incident.

Most of the above issues are cost related. Why do we knowingly place other people’s lives on the line, along with our neck on the chopping block just to save some costs that only degrade skills and safety?

My opinion is that quality equipment, remote switching, interlocks and PPE are tangible items we know work, will last and you can clearly see the value.

It’s hard to find value when investing in skills in people who move on, don’t care, don’t learn, don’t apply what they learn or weren’t effectively taught. Additionally, investing in a trainer who does the minimum work, doesn’t have the required skills or experience, can’t answer questions and can’t explain things in easy terms, means none of your team, including the good ones, won’t develop or gain decent skills anyway.

You can be forgiven for deciding that tangible investment is the most logical way to go. Let’s look at the control measures we employ.

Arc flash suit

The most popular control measure and still, misunderstood.

Besides admin procedures, arc flash suits are the oldest, cheapest and most common control option. When I say oldest, it has only been around these past two decades and is widely popular in just the past ten years or so.

Although it is universally accepted as a requirement when switching HV equipment, I still hear comments like: “The day I have to wear an arc flash suit, is the day I retire” or “We don’t need to wear an arc flash suit with our equipment.”

I consider the first comment to be on par with those 40 years ago that said: “I have been working for 50 years without safety glasses and nothing has happened.”

Although it is highly unlikely you will ever be involved in an arc flash incident, there is still that possibility and you never want to be thinking “if only”.

It takes just 15 minutes to put on, you’re paid by the hour and the suit is provided free of charge. Why should anyone risk their skin to save the company 15 minutes?

As for the second comment, personal protective equipment (PPE) is worn in case the equipment fails and equipment fails all the time. The only time we would never bother wearing an arc flash suit is when operating remote switching from a separate room.

Interlocks

Interlocks are an attempt to prevent mistakes and a lot of reliance is placed on this safety measure. Interlocks come into play if the operator tries to operate the wrong equipment and that is only if the interlock has been designed correctly.

Many interlocks are easily defeated, even inadvertently, rendering them effectively useless.

If you rely on interlocks to prevent an arc flash, you’re playing a game of arc flash roulette.

Remote switching

Remote switching is a vital, low-cost solution for operator safety. Short of eliminating switchgear altogether, remote switching is the safest option the industry has to protect the switching operator.

For decades, we have had the option of attaching all kinds of machinery to the front of boards so we can operate the equipment from a safe distance. It doesn’t need to be an expensive commercial solution and there are many unfounded ‘homemade’ solutions that incorporate ropes and pulleys. If the solution moves you away from the board, it’s a great idea.

In the past five years, we have seen an explosion (no pun intended) of brilliant hard-wired and even wireless remote switching systems installed on sites. In my opinion, this is a must for all sites.

However, even remote switching only protects the switching operator. It does nothing to prevent the operator from switching the wrong piece of equipment. It does nothing to ensure the correct piece of equipment is isolated. It does nothing to protect anyone else in the system. It does nothing to prevent inadvertent shutdowns or destruction of equipment.

Detection

Arc flash detection is a must-have in all systems.

Ten years ago, at a mining conference, I was introduced to the advancements being made in fast arc flash detection and tripping. The technology is there, it’s proven and should be installed whenever possible.

Arc flash detection will recognise the initial arc and trip the breaker before the air becomes ionised and propagates into a full arc flash incident.

The incident energy level should be limited to less than 1.2cal/cm², making it a survival event and limiting the amount of property damage. But again, the horse has already bolted when the protection device operates.

Too often I hear of HV systems tripping when an incorrect operation was executed. Too often this is considered a near miss, and it is back to business as usual.

The problem you now face is the equipment may well be compromised. With the high current surge on the system long enough for the protection to trip, users must consider the number of times the system will survive such abuse until it will no longer sustain it long enough for the protection device to operate.

The protection system has compensated for the operator making a mistake, this time, but what about the next time? Is the equipment still rated to withstand the site’s prospective fault current?

Construction

In a perfect world, where equipment is perfectly designed, manufactured, tested, installed, commissioned and operated, equipment shouldn’t fail… but it does. There are several steps in the manufacturing process and all it takes is one slight error and there’s a crack waiting to be opened up.

A good friend of mine was investigating an equipment failure not too long ago. Everyone had given up the search for the cause, but he wasn’t going to let it beat him. He stripped down every component to its minute individual pieces and discovered a tiny flaw in one component that had been there since the unit was manufactured more than ten years earlier. That minor flaw causes hundreds of thousands of dollars in damage and repairs.

There’s most likely no need for arc flash clothing when operating on a switchboard that’s less than five years old, certified as type tested, you have the certificate to say 65kA and it is installed on a site where the maximum fault level is 40kA. However, I support anyone who would still want to take all appropriate measures just in case there’s a small, unnoticed error outside of your control.

Commissioning

I have seen – and I am hearing of – far more issues with new equipment. Fake welding, loose connections, overtightened bolts, incorrectly connected test points, rubbish left in panels, missing components, control equipment installed overseas incompatible with Australian equipment and communication protocols and so on.

When I switch new equipment on site, it’s common for it to fail.

It will usually operate fine for maybe half a dozen times, but then an interlock fails, an earth doesn’t open, a semaphore fails to operate, or an interlock incorrectly prevents access to a switch. Most of the issues aren’t capable of or have the time available to check during commissioning.

I can’t emphasise enough that when you approach any equipment, always consider there are nine things wrong with the equipment and you don’t want to make that small tenth step that brings all those issues together in one spectacular uncontrolled incident.

The forgotten control

The forgotten control measure is understanding. HV operates need to understand:

• Their equipment
• Their system
• The ever-changing hazards in HV
• The effect switching has on the system
• How to manage your HV system
• How to switch safely
• How to isolate safely

A close friend and HV trainer and consultant often says: “If you understand how to manage the system, how to read the hazards, how to read your drawings and wear your PPE, you will be perfectly safe.”

Understanding is key.

If you understand how to switch safely, the interlocks will never activate, you won’t remotely operate the wrong piece of equipment, you won’t earth an energised cable, you won’t remotely isolate the wrong piece of equipment, you won’t harm anyone else on the system and you won’t damage upstream or downstream equipment.

Learn how to plan, prepare and perform HV switching properly in the first place and incorporate all the other controls as a backup. Your life, and the life of others, requires you to become a specialist in HV.

The philosophy of a HV specialist

To become a specialist in HV, you need to understand why you operate, before understanding how to operate. Why operate a particular piece of equipment? What effect will it have on the system? Why must you operate it? And how do you operate it?

Too much focus is spent on training people on how to operate switchgear long before operators are capable of recognising the hazards created by switching HV systems.

Many incidents aren’t caused by people not knowing how to operate switchgear, they operate them perfectly. The issue is that they operate them at the wrong time in the wrong sequence.

Don’t let them near the switchgear until they are fully aware of the electrical hazards. Spend 80% of the time training them on electrical systems and 20% of the time on how to push buttons and turn handles.

We say that “people are our best investment” and we can be forgiven for not meaning it. With an ever-increasing transient workforce, our lasting investment seems to be our equipment. The investment in our people has been restricted to only that which is a legislated requirement.

We try and make our equipment foolproof; anyone who comes to the site will be able to operate it safely. I don’t think that is ever going to be the case. And AI is definitely not the solution.

I’m not proposing that investing in our workforce will solve the transient issues; there are many factors involved with retaining passionate specialists. But it can be done. There are a lot of people out there, FIFO workers have been working in the very same remote, barren, unforgiving environment for decades.

Focus on developing disciplined specialists. Sell people on the idea of why you are investing in them, what you want them to achieve, why the training is important and how it will benefit their job and their life. Show them they are more important than your equipment and it will be hard for anyone else to entice them to leave.

Your people will last longer than your equipment and will truly be your best investment.

The very best control measure for mitigating HV risks is developing your operators into HV specialists; know why they are operating, operate the equipment in the correct sequence properly in the first place and all the other control measures will be a backup.

Fewer unplanned outages, fewer interlock operations, fewer tripping, fewer switching surges, fewer risks of equipment failures and your equipment will last longer.

Your people will feel safer, less stressed, more confident, more included and happier to perform their jobs.