Grounding Rod Requirements: What Can Be Used?
The first thing that needs to be understood is that there are two types of grounding rods available today; stainless steel and aluminum. Stainless steel rods have been around longer than aluminum ones. They are easier to work with, but they do not last forever. Aluminum rods have become popular lately because they are lighter weight and less expensive. These advantages make them better choices for many applications.
Stainless Steel vs. Alumilite
Aluminum rods are made from aluminum oxide (aluminosilicate). There are several grades of aluminum oxide, which vary in strength and hardness. Some grades of aluminum oxide are stronger than others. For example, the most common grade is A1, which is known as “superior” or “high quality.” Higher grades of aluminum oxide are stronger than lower grades.
The higher the grade, the harder it is. The hardest aluminum oxide is called “A2,” and it’s considered very hard. An alloy of aluminum oxide and magnesium makes an even tougher metal called “A3.”
What Is Staying Power Of Aluminum Rods?
Staying power depends on three things: the type of aluminum rod, its thickness, and how long you use it for.
Type Of Aluminum: The longer the rod is in the ground, the more susceptible it is to corrosion. Most aluminum rods have a protective surface coating, which prevents them from deteriorating. Over time, that protective surface coating will wear off, after which time the aluminum will begin to corrode. This process takes years to happen, but it will eventually take place.
Thickness: Thicker rods are harder to cut and bend. To compensate for this, the manufacturers usually use a lower grade of aluminum that is more susceptible to deterioration. For example, a 1/2-inch thick rod may be made from A1, while a 5/8-inch rod may be made from A3.
Use: The longer a specific type of aluminum rod is in the ground, the faster it will succumb to oxidation and corrosion. The same 1/2-inch thick A1 rod, if used for grounding an outlet for a few years, may only last a few years before corrosion makes it unsafe. On the other hand, a similar 5/8-inch thick A3 rod may last 20 years or more in the same application.
Requirements For Grounding?
For proper grounding, you need the right size and type of wire, and the right size and type of ground rod. We’ll assume you know how to calculate the size of wire you need, and we’ll also assume you know how to cut and thread the wire for easy installation. So, let’s talk about ground rods.
There are two types of ground rods: galvanized steel and aluminum. Galvanized steel ground rods come in several sizes, from 1/2-inch up to several inches. Galvanized steel rods are stiff and hard to install, and they will eventually rust if left in the ground. Galvanized steel rods are inexpensive and plentiful, however, so many people use them despite their shortcomings.
Aluminum rods are softer, lighter, and easier to bend. They come in several sizes as well, from 1/2-inch up to several inches. Aluminum rods do not rust, so they don’t suffer from the shortcomings of galvanized steel rods. They are more expensive and less plentiful than their galvanized counterparts, so many people don’t use them.
The right size ground rod depends on the size of wire you’re using. We won’t go into that here, but the rule of thumb is: use the largest ground rod you can get away with. The larger the ground rod, the better the ground.
How To Use A Length Of Wire As A Ground?
You presumably have a length of bare copper wire with one end stripped and the other end tucked into an outlet box. You now need to connect that wire to a metal water pipe. There are several ways to do this.
Soldering: The easiest way to connect the wire to the pipe is through soldering. Before you start, turn on the tap closest to where you’ll be working. Bring out your soldering iron, and a container of water. Wet the pipe with water, and run the hot soldering iron over the wet spots.
This will create steam, which will make it easier to slide the wire onto the pipe.
Wrapping: If you don’t have experience soldering or don’t want to bother, you can also wrap the wire tightly around the pipe. Use pliers to secure the wire in place. You’ll have to wrap the wire more than once to make the connection secure.
Clamps: An easier way to wrap the wires is to use clamps. These are made especially for connecting grounding wires to pipes, so you won’t be able to use them for other types of projects. You can find these at hardware stores, and they come in several sizes. Just like with wrapped wires, you may have to use more than one clamp.
Crimping: The easiest way to connect the grounding wire to a pipe is to use a crimping connector. These come in several sizes, so you’ll have to match the connector size to the gauge of your wire. The connectors are reusable, so once you’ve matched the connector size to the wire size, just slip the connector over the wire, and then slide it up against the pipe. Give it a squeeze with some pliers, and you’re done!
That’s it! Follow these steps, and in no time you’ll have your grounding wire connected.
Remember: Always be sure to ground your system before applying power. If you don’t, you risk getting a nasty shock, or even damaging some of your equipment.
Always make sure all of your ground connections are tight and secure. If a ground connection is loose, you risk having an intermittent connection. Intermittent connections will cause a great amount of electronic noise to be present in your sound system, which will definitely affect the sound quality of your music.
Once you’ve connected your grounding wire, you’re ready to hook up the rest of your equipment!
Continue to Cable Ties & Grounding Bushes.
Back to Installing an Audio System.
Back to Installer Training.
Sources & references used in this article:
Acoustic guided wave techniques for detecting corrosion damage of electrical grounding rods by J Zhao, N Durham, K Abdel-Hadi, CA McKenzie… – Measurement, 2019 – Elsevier
Practical evaluation of ground enhancing compounds used in grounding rods by RW Drisko, AE Hanna – 1970 – NAVAL CIVIL ENGINEERING LAB …
Analysis on influence of long vertical grounding electrodes on grounding system for substation by A Galván, E Gaona, G Pretelín – X International Symposium on …, 2009 – researchgate.net
Driving tool for tubular grounding rods by R Zeng, J He, Z Wang, Y Gao, W Sun… – PowerCon 2000. 2000 …, 2000 – ieeexplore.ieee.org
Natural materials as grounding filler for lightning protection system by HC Daniels – US Patent 2,147,829, 1939 – Google Patents
Evaluation under controlled conditions of ground enhancing compounds used in grounding rods by J Jasni, LK Siow, MZA Ab Kadir… – 2010 30th International …, 2010 – ieeexplore.ieee.org
Grounding system cost analysis using optimization algorithms by AD Galván, DM Soto, JMG Malo – International Symposium on …, 2009 – researchgate.net
Improved design of square grounding grids by JW Perng, YC Kuo, SP Lu – Energies, 2018 – mdpi.com