Maximum Resistance allowed-reading

[egurdian2]

Guys,
Can anyone tell me if there's a specific requirement (NEC) for Resistance readings on a grounding system? -Or is it a recommended/specified level depending on the application?

 

[charlie b]

That is a design decision, and is not addressed by the NEC.

 

[egurdian2]

10x4, thank you.

 

[Sdr96]

Consider 250.56. A single electrode needs to be less than 25 ohms or augmented with an additional electrode.

 

[raider1]

Consider 250.56. A single electrode needs to be less than 25 ohms or augmented with an additional electrode.

250.56 only applys to a single rod, pipe or plate electrode. This section only requires the electrode itself to have a resistance of 25 Ohms or less or be agumented, it does not apply to the grounding electrode conductor or any other part of the grounding system.

Chris