Keep tabs on your electrical distribution

The electrical distribution system in a plant is a lot like oxygen: You only tend to think about it when it’s not there. But just like oxygen, the electrical system is vital to your company’s life. Applying the same rules to checking an existing system and building a new system ensures that you don’t find yourself in trouble in the long run.

By Charles Skinner

The electrical distribution system in a plant is a lot like oxygen: You only tend to think about it when it’s not there. But just like oxygen, the electrical system is vital to your company’s life. Can you imagine your plant without energy? Neither can I, but because you probably haven’t given your electrical system much thought lately, there may be problems lurking in your grid. Applying the same rules to checking an existing system and building a new system ensures that you don’t find yourself in trouble in the long run.

If your facility has made no major electrical upgrades and is operating problem-free, you are in the minority. All facilities have safety-related problems, even if managers don’t know it. Electrical problems can be as simple as code noncompliance that is overlooked on a daily basis. Examples include using an extension cord in place of installing permanent power, or installing incorrect wiring in areas that require fire protection techniques.

But they could be even more serious. For example, when was the last time that you verified that main or branch circuit breakers still operated properly? Just because the breakers haven’t tripped in a long time doesn’t mean they’ll be able to work properly when they should.

Few companies have used thermographic technology on electrical equipment to detect lingering problems. Some have installed new equipment that required an electrician to make the connections, but never applied for a permit and didn’t have the installation inspected. These actions and omissions can expose a company to huge future problems.

Managing a safe plant electrical distribution system requires constant attention, but this is something that many people rarely have time to do. But we humans have the capability to change our ways. Now is the perfect time to start thinking about your electrical system and what it may need to continue to function safely. Following are some actions that will determine your plant’s level of safety.

Check the existing configuration

Verify that your plant’s physical layout is really optimal for the purpose, and that the electrical systems are designed by a registered professional engineer. If the plant isn’t laid out efficiently, or if the electrical systems aren’t certified, this is the time to develop a new layout and to have your existing system reviewed to ensure it’s up to snuff. The most common standards that apply to electrical system installation are NFPA 70 National Electrical Code and, for Canada, the Canadian Electrical Code CSA C22.1.

The good news about NFPA 70 is the codes were developed using a consensus format, which means that anyone who sees a problem in the content can propose a change. It also means the codes are realistic, so you won’t find that the documents require something outrageous. Companies that build electrical components and equipment also reference the NFPA 70 code. If you use these codes to design or redesign your electrical distribution system, you’re incorporating ideas that will mesh with the safety designs of the machines and equipment you’re using.

Determine any modifications

Once you’ve determined that your systems meet NFPA 70 codes, determine whether your system requires additional modifications to meet local codes. You’d be surprised at how requirements vary from municipality to municipality.

It’s important to remember that your local electrical inspector isn’t your enemy. Instead, the smart plant manager sees them as a tool that can be used to the company’s advantage. The local inspector’s job is to help you make the design and installation of your electrical distribution system as safe as possible. Following their advice will save the company time and money by avoiding any discrepancy between what is expected and what is required.

Design the system

It’s common for a company to hire a registered professional engineer to design the electrical system. It’s common for that design to be handed to a contractor to furnish and install the equipment and wiring shown in the drawings. Also, it’s common to leave the local electrical inspector out of the loop, and that’s a big mistake.

When the local inspectors finally are brought in (typically after the design is completed and in the process of being built) they’ll find issues that will require design revisions. This slows down the job, adds cost and engenders hard feelings between the company and the inspectors. Getting the local people involved as early as possible avoids problems.

Check the machinery

After designing your electrical distribution system, focus your attention on the machinery and equipment. This is especially important if you’re thinking of buying new equipment or are considering moving existing equipment.

If you’re adding new machinery that has been imported from a foreign country (and, in some cases, even domestic machines have this issue), you’ll need to ensure that the hardware meets the requirements of OSHA and National codes. This doesn’t simply mean verifying the machinery has a CE Mark because this mark isn’t considered a third-party label as required by OSHA and most local inspectors.

The federal government, under OSHA 29 CFR 1910.301 (Subpart S), governs “...electrical safety requirements that are necessary for the practical safeguarding of employees in their workplace.” Simply put, this means that the electrical equipment in your plant must be recognized by the assistant secretary of labor as evidenced by its listing and labeling by a recognized testing lab.

Older equipment

This same issue holds true for old equipment being relocated within a plant or moved from another site within the company. Sometimes the local inspector will require that old equipment be brought into compliance with current local and national codes. Even if that old machine has been working great, once you move it, it will probably need to have a safety assessment. This may mean making it conform to standards it was never originally designed to meet. In both cases of new and old equipment, if the correct certifications aren’t achieved, this machinery becomes like a car that’s not certified by the U.S. Department of Transportation: you can drive it, but it’s illegal to do so.

Stay proactive

It’s especially important to remain vigilant when it comes to the safety of your plant’s electrical distribution system. Because it’s out of sight, it’s out of mind, and when systems are neglected, problems fester.

Everyone pays attention to the obvious factors such as mechanical safety systems or simple things such as wet floors. When was the last time you acted proactively and thought about the safety and design of your electrical distribution system? This is something you’ll need to get in the habit of doing if you want to operate a truly safe plant.

Charles Skinner is program manager for Field Evaluation Services at TUV Rheinland of North America Inc., San Diego. Contact him at (760) 929-1780.

Show Comments
Hide Comments

Join the discussion

We welcome your thoughtful comments.
All comments will display your user name.

Want to participate in the discussion?

Register for free

Log in for complete access.

Comments

No one has commented on this page yet.

RSS feed for comments on this page | RSS feed for all comments