Grounding Systems — protecting your PSAP against lightning and power surges

Your emergency response center is a critical hub for community health and safety deployment. To do your job, you rely on a complex network of software, supported by hardware that connects to the building power. The electronic equipment you rely on faces three major power-interruption dangers: lightning, static electricity discharge, and electric al surges. Improperly grounded equipment can be damaged, data can be lost, and the vital services that you provide can be disrupted.

According to experts at Electrical Construction & Maintenance, it only takes 25 electrostatic volts to irreparably damage an integrated circuit.*

And Markel Specialty Insurance shares:

A brief history of ground

Before the widespread use of grounding electrodes, any electrical equipment connected to the circuit would be fried beyond repair, and in the worst case scenario the tremendous heat generated by the lightning strike could cause fires. Some of those fires caused grave injury and decimated structures.

Discovery of the electricity “ground” is linked to telegraph systems. Long distance telegraph systems, first developed in the 1820s, originally were built with two wires—a sending and a return. It was later discovered, that a second wire connected to the earth channeled energy out of the device; it was "grounded." The new discovery made the return wire unnecessary. Not only did this solve the electric overload problem, as you might expect, it saved a lot of wire and a lot of money.

As electrical technology progressed and the danger of lightning and unexpected electrical surges were better understood, grounding electrodes (or earthing electrodes) were developed to channel the electrical overload into the earth where it could harmlessly dissipate.

In the 911 Dispatch and Operations sectors, there are specific protocols, standards and certifications designed to assure (1) prevention of power disruption and (2) system backup in the event that primary measures fail. Are you familiar with your industry’s grounding protocol standard?

The Motorola R56 standard

Large radio towers and antennas are natural targets for lightning and electrical storms. Moreover, proper grounding is essential to mitigate crosstalk and power supply noise when using radio communications.

To address this major issue and ensure their emergency services communication equipment is operated under the best possible conditions, Motorola developed extensive standards and guidelines for safety issues related to both shock hazards and lightning strikes.

These standards were released in Motorola Publication R56 “Standards and Guidelines for Communication Sites.” This standard has come to be known simply as Motorola R56, and its thoroughness has led to it becoming the de facto standard for electrical grounding.

When specifying console workstations, your buying team should ask how to best incorporate grounding measures that meet the R56 standard.

Furniture Materials and Impact on Conduction

Steel vs. Wood

While communication centers prepare their furniture with grounding bars, in the case of a ground disruption, conductivity of surrounding materials may knock out critical technology.

A major advantage that Watson Consoles provides to customers is non-conductivity: the primary building material is wood.

Twenty-five years ago, the gold standard in emergency dispatch furniture was steel (and the primary technological tool was the typewriter). Steel furniture held up well. It was heavy. It was perfect for the everyday wear and tear of unrelenting, 24-hour per day use.

It’s also an amazing conductor of electricity.

That’s not something that matters when your primary tool is an IBM Selectric. But when you’ve got eight monitors, ten CPUs and a couple of servers at every workstation, a highly conductive surface surround can cause a lot of problems.

To ground metal-based furniture, you must first connect the building ground into a copper grounding bar housed within the undercarriage. For metal-based furniture, everything that's metal within the furniture has to be ground to that same grounding bar. All of the end-user equipment must also be ground, but they must be ground independently from the metal furniture. This can be complicated and expensive.

Wood construction is not as demanding. The only thing that needs to be grounded within the system are power distribution units and end-user equipment.

When console workstation providers simplify the grounding requirements for the end user, centers save money that would otherwise be spent on additional grounding systems and hourly electrician charges.

(To learn about additional benefits of wood-core materials in dispatch consoles, read our series Which is the best material for your dispatch console, wood or steel?)

You should also ask your console supplier if their units are UL962 certified. UL 962 certified consoles, like Watson Console’s Mercury have been tested by a third party for electrical safety. In the case of Mercury, a single point power connection grounds directly to the main building power, which means no additional grounding is required for the furniture.

Understanding your center's grounding needs - light vs. heavy

Why is it important to simplify grounding requirements? Because grounding bars are not cheap. Their conducting material is top-grade copper, and the price of copper remains high. If an emergency response agency can avoid paying more than necessary for each workstation, they should. Those critical dollars can be put toward additional equipment that enhances 911 communications efficiency.

That said, with a single emergency response agency likely housing a half million dollars worth of electronic equipment (or more!), under-protecting is simply not an option.

Every center design is unique, and most of them can be divided into workstations that require either light or heavy grounding. Before deciding on the console workstations you will put in your center, consider the level of ready-to-work grounding capability that is provided.

Your center’s needs may be different now than they were ten years ago and will likely be different than the center in the adjacent jurisdiction. The type of calls you field and operations you oversee will also impact the level of grounding required for safety. For example, a small police station will typically need a light grounding system since their workstations only need eight connections. By contrast, at a major airport a workstation might need 16 to 24 connections to accommodate their equipment.

Planning for the future

Technology gets more affordable every year. And the kinds of systems used by the largest airports may make their way into small police departments in five to seven years or less. That means those small departments may need to ground 16 to 24 connections in only a few years from now.

Choosing console workstation and furniture assets that are designed to support increased technology needs is a smart choice for 911 and Operations Centers.

At Watson Consoles, we know we can be a part of that solution. We believe that furniture systems must be designed for your needs today and capable of meeting your changing needs tomorrow.

That’s why Watson designs consoles like Mercury - the modular design and single-point main power connection provides your center a flexible asset . If the number of equipment connections you used in the future increases the system grounding need from light to medium or heavy, simply swap out the grounding bar in your Mercury console. There will be no need to re-run a grounding system for separate metal housing which is required of other manufacturer’s designs. Choosing a Watson console means your grounding requirements will be met today and easily maintained for years to come.

When auditing or planning your center console and technology layouts, challenge your vendors to help you defend against static electricity and power-surge damage. Remember, furniture and flooring providers are a first-line defense.

And enlist a qualified consultant and electrician to create a grounded system that meets R56 standards and will support near-term technology and power expansion.

In our next Tech Trends installment...

In the first installment we talked about current monitor preferences and emerging trends, and the functional impact of changing technology on array bars and mounting systems. Today you learned about the importance of grounding and how your console workstation suppliers can contribute to safe and easy-to-maintain power distribution.