Let's break down these questions related to grounding electrode conductor (GEC) requirements.

Question 1: GEC tap to common electrode conductor via busbar connection?

Without seeing the picture, it's impossible to definitively say if it complies with 250.62(D)(1)(3). However, your assessment of it looking more like a jumper than a tap is likely correct, given the context. Here's why: 250.62(D)(1)(3) allows for tapping a GEC to a common grounding electrode conductor (GEC) through a busbar. The intent is to create a central grounding point. A "tap" in this context implies branching off the main conductor. The main GEC carries the fault current back to the source. The tap is simply a connection point. If it's a "jumper," it's more likely connecting two parts of the grounding system, rather than tapping a single main GEC.The key question is: Is this connection serving as the primary grounding electrode conductor for one or more service disconnects? If it is, and it's connected to the main GEC via a busbar, it could be compliant. However, if it's only connecting two grounding electrodes, then it's not acting as a tap to a common GEC via a busbar.

Therefore, based on your description of it looking more like a jumper, it's less likely to be a compliant tap. It is more likely that you have a common GEC for each disconnect connected to a common grounding electrode like a ground rod. If these two separate GECs are only connected to each other via the ground rod, that would not satisfy 250.62(D)(1)(3).

Question 2: Multiple GECs to a ground rod, then a jumper to a second rod?Yes, you are correct. If you have separate GECs from multiple disconnects, both connected to the same ground rod, and that rod is part of a supplemental two-rod system because you need to achieve 25 ohms or less, then you only need one 6 AWG copper jumper from the first ground rod to the second ground rod.

Here's why: The purpose of the 6 AWG jumper is to create the supplemental grounding electrode system. It ensures that the two ground rods are electrically bonded together. The NEC allows parallel paths for ground fault current. Having multiple GECs to the same ground rod doesn't change the fact that you only need one connection between the two rods in the supplementary system. The 6 AWG jumper acts as a common bonding jumper for the grounding electrode system.Important Considerations



Connection Method

Ensure all connections (GEC to rod, jumper to rod) are made with listed and suitable connectors.

Burial Depth

The supplemental ground rods must be buried at least 8 feet deep (or the top of the rod must be at least 8 feet below grade).

Spacing

The supplemental ground rods must be at least 6 feet apart.

Testing

It's always a good practice to test the grounding electrode resistance to ensure compliance with 25 ohms or less.

Disclaimer: I am an AI chatbot, and this information is for general guidance only. Consult a qualified electrician or refer to the latest edition of the NEC for specific code interpretations and requirements in your area. Flag for review