In the first post in our railway electrical protection blog series, we described the harm that lightning strikes can cause to rail properties, and highlighted how nVent direct strike lightning protection systems help to prevent and mitigate damage caused by severe electrical surges. These solutions are the first tenants of the nVent ERICO Six Point Plan of Protection, which are to (1) capture the lightning strike, and (2) convey this energy to ground. This second tenant leads into grounding and bonding, which is one of the most important aspects of the Six Point Plan of Protection, and essentially the foundation of nVent ERICO railway electrical protection solutions.
Railways have complex electrical systems and require proper grounding and bonding throughout the network. In addition to leaving wayside equipment susceptible to damage, the lack of a proper grounding system poses a serious safety risk to rail workers and the general public. Electrical energy needs to be dissipated into a grounding system or else the current will stray to places where it shouldn’t appear, leading to touch/step potential injuries. This can happen anywhere that exposed metal exists in the network if there isn’t proper grounding and bonding. Stray current can cause other hazards that put rail workers and the public at risk, especially in transit networks where vehicle traction is powered by high voltage electrical current. Specifically, networks powered by contact rail (third rail) are uniquely susceptible to fires caused by electrical arcing incidents that spark combustion and ignite flammable debris. While there are many causes of arc flash fires, improper grounding and bonding can contribute to these incidents, which can in some cases be catastrophic.
The following are components of the rail network that are generally require grounding and bonding:
- Running rails
- Overhead catenary and contact rails (third rails)
- Wayside equipment (interlockings, switch machines, intermediate signals, etc.)
- Electrical/electronic enclosures throughout the network
- Communication towers and microwave installations
- Grade crossings
- Building and support facilities
- Onboard rolling stock
nVent ERICO offers a wide range of grounding and bonding solutions for rail infrastructure, wayside equipment, as well as facilities and structures. After lighting strike protection, the proceeding tenants of the nVent ERICO Six Point Plan of Protection are focused on grounding and bonding, providing a strategy to (3) dissipate the energy into the grounding system, and (4) bond all ground points together. Our comprehensive line of grounding products include:
- Ground Conductor, Ground Rods and Ground Mats, including solid copper, copper-bonded steel, as well as stainless and galvanized steel
- Grounding Plates designed to protect aluminum structures such as signal bungalows
- Ground Enhancement Material, a carbon-based material that improves overall grounding effectiveness, especially in areas of poor conductivity, by covering the trench/ground rod, and mixing in with the surrounding soil
- Potential Equalization Clamps, equipotential bonding devices that join together separate ground systems to create an equipotential plane that prevents differences in voltage from developing
- Ground Resistance Tester Kits, ultra-light-weight and portable, these devices assess ground conductivity, which is an important first step in creating an effective grounding
With a comprehensive line of grounding and bonding products, and the coordinated approach of the nVent ERICO Six Point Plan of protection, nVent ERICO is an industry leader in railway electrical protection that provides essential safety for rail workers and the public.
Learn more about nVent Railway Electrical Protection. Read the next post on SPDs (surge protection devices) for railway properties.