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	Subject - Office Bldg./House panel grounding? JerryB52 This is the situation, a job was recently dumped in my lap to finish. I have a house meter with a 350 MCM neutral and a 1/0 ground back to the grounding system. The 350 MCM neutral in the house panel is bonded to the can. Do I need a separate grounding conductor from the house panel to the grounding system or does the neutral suffice? I feel that I need to run a 1/0 grounding conductor to the grounding system, but my project supervisor said it wasn't needed. Thanks for the help... lctrc789 I am assuming this is a large home LOL. But are you saying that the neutral conductor is landed in the meter base and then to the panel and then from the panel you have a 1/0 to the ground. Where is the 1/0 come from the panel or the meter base. I know many counties are different, however I would say that by the NEC the neutral must be bonded to the meter base and the panel and the grounds have to come form the main panel to your grounding sytem for a complete bond. I am not sure what you mean here, as far as where your ground is connected to. JerryB52 The neutral is bonded in the meter can with a 1/0 to the grounding electrodes. From the meter to the House panel, which has a main in it, I have the 3- 350 MCM phase conductors and the 350 MCM neutral that is bonded to the panel. What seems strange to me is that whoever installed this panel, didn't bring a grounding conductor from the grounding system to the panel. Would the bonded neutral in the house panel be a sufficient ground??? lctrc789 Not the way we do it here, Because the Main panel must be grounded at the Main neutral. If you rely on the ground at the meter only then the only thing that is grounded is the meter base not the service. I know that through the neutral it is technically grounded and years ago that would have sufficed, but not now not here and in many localities. All things I have been taught on grounding by article 250 of the NEC states that all grounds must go back to the main and the main neutral bar. As many grounds as you can have i.e. ground rod, water ground etc. the more the bettr. Pierre Belarge Pat You mention that the GEC has to be connected to the main neutral. 250.24(A)(4) permits it to be connected to the EGC bus or the grounded conductor bus if it meets the requirements set forth in this subsection. Pierre