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What Grounding Standards are there for the installation of high-tech equipment, particularly Audio-Visual gear?

Hi Alex,

Thank you for your question regarding Grounding Standards for installing high-tech equipment in existing buildings.

There are many different standards in the industry that may apply to your industry, unfortunately none are specifically tailored to meet your needs.  Often when installing sophisticated and sensitive electronics systems, particularly those in the Audio-Visual field, electrical-noise, transients, and harmonics can adversely impact both the performance and the quality (poor sound/visual) of the equipment.  In recording rooms, 60Hz hum is a big concern, and proper grounding is the answer.  To solve these problems it often requires a low resistance grounding electrode, and an isolated noise-free ground path.  The trick of course is how to install these systems in existing buildings while keeping costs down.

Writing a specification for construction that is actually useable and doesn’t require the contractor to dig through hundreds, if not thousands of pages of standards, is a task in its own right.  While one could easily list a series of grounding standards (IEEE Std-142, IEEE Std-1100, NFPA 70, ANSI-TIA/EIA-STD-J-607-A, Motorola R56, etc.) and just hope the contractor can pick out the applicable pieces for your project, it is generally far better to provide the GC with an actual task list that can be quoted.  The truth is, no contractor has the time to dig through all these standards and figure them all out.  It would literarily take weeks, and would probably only result in a no-bid.

Here is what we recommend you do for a simple specification standard for your installations:

The General Contractor (GC) will hire an engineering firm specializing in electrical grounding to provide a work plan for the following:

1. The installation of a dedicated 5-ohm or less resistance-to-ground electrode.  This will require Wenner 4-point testing and a computer model.

2. To provide a noise-free ground path from the newly installed equipment back to the electrode

3. To provide a ground path from the new isolated ground system back to the first-service disconnect as required under the National Electrical Code (NEC)

4. To analyze the existing electrical system for problems and power quality issues, and make recommendations for isolation transformers and/or UPS systems as needed to protect the new equipment.  This will require the monitoring of the incoming utility power with quality analyzers.

5. To make recommendations for the proper grounding of the computer and server systems associated with the new equipment.  ANSI-TIA/EIA-STD-J-607-A will be a guideline document.

6. To analyze the building infrastructure systems to see what other factors may impact the new installations (improper neutral-to-ground bonds, improper water pipe connections, Edison circuits, lightning protection systems installed to close, vapor barriers under the concrete, delta-transformers, high-voltage systems nearby, etc.)

While it would be nice to simply have a single standard to hand to a GC, there are simply too many factors for any single standard.  This is why the Code of Federal Regulations (CFR) Title 29 Subpart 1910.269 Appendix C, takes the same approach and mandates that engineering firms specializing in electrical grounding be contracted when dealing with human safety issues such as Step & Touch voltages.  The issues are simply too complex and must be analyzed professionally.

I hope you find this information useful, if we can be of any further assistance, please do not hesitate to call.

Best regards,

The Engineering Team at E&S Grounding Solutions

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