Thank you for your question regarding electrical grounding for multiple buildings, it is our pleasure to help.
When you have multiple building being fed from a common power source (first service disconnect), you must have one common grounding system. This is required under the National Electrical Code, the IEC, and every known electrical standard. This is vital so that Over Current Protection Devices (OCPD) such as fuses and circuit breakers will function properly.
Even if your site does have several separate first service disconnects, you will only benefit from having a common grounding grid. Computer data lines, telecommunication systems, etc. will be tied between the various buildings, and a common ground grid will ensure that there are no differences in potential that could cause damage to sensitive electronic equipment.
We hope that this has answered your questions. Please do not hesitate to contact us again should you have any further needs.
The Engineering Team at E&S Grounding Solutions
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