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Isolated Ground Design and Standard

Isolated Ground Receptacles

Definition of Isolated Ground

NEC Article 250.148(D) : A receptacle installed for the reduction of electrical noise on the grounding circuit, the grounding terminal shall be connected to an insulated equipment grounding conductor run with the circuit conductors.A true dedicated line with IG consists of four individually isolated wires (line, neutral, ground and isolated ground) that are run from the electrical panels to the isolated ground receptacle.

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Isolated Ground Receptacles

Why Use an Isolated Ground Receptacle

To provide a noise-free ground return, separate from the equipment grounding return. The IG receptacles are used in situations where we wish to avoid the mixing of sensitive equipment ground and the building power system ground at all points except the power source.To protect electronic equipment, such as computers, hospital equipment, and audio equipment. A lot of the equipment providers require IG receptacles.The use of IG helps eliminate the potential for a "ground loop", which can cause noise, data errors, and disruptions to these systems

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Isolated Ground Receptacles

Isolated Ground Receptacle

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Isolated Ground Receptacles

Normal Receptacle

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Isolated Ground Receptacles

Isolated Ground Receptacle

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Isolated Ground Receptacles

TES Standard For 480V services

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Isolated Ground Receptacles

TES Standard For 208V services

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Isolated Ground Receptacles

TES Standard For Existing services

Add an isolated ground bar in the existing panel and provide all required grounds to the existing transformer or existing service ground point.Look at the pictures of the panel to verify you can add an isolated ground bar and can connect to existing grounding system. Talk to the senior level engineer, and possible the manufacturer’s rep.

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Isolated Ground Receptacles

Any Questions

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