250.56 Resistance that Rod, Pipe, and also Plate Electrodes. A solitary electrode consisting of a rod, pipe, or plate the does not have actually a resistance to ground the 25 ohms or much less shall beaugmented by one added electrode of any of the varieties specified by 250.52(A)(4) v (A)(8). Where multiple rod,pipe, or plate electrodes are installed to meet the demands of this section, lock shall no be much less than 1.8 m (6 ft) apart.

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How does her jurisdiction law that password section? execute they call for a second rod at any time a solitary rod is required?When I create the correction, I always spell out the word "feet" together in "a minimum 6 feet far from the very first rod"I still gain these:
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For business changes and upgrades or new installations the don"t have actually rebar in the footer, we always see 2 floor rods since of the exact same reasons declared above. 1) Not many have the equipment necessary to test and 2) Those that do have actually a difficult time gaining 25 ohms or less with our soils.Here is a quick story that I will certainly make long.I was always under the impression that if you had a water pipe the qualified together a grounding electrode, climate if you included a stick outside, the was the 2nd electrode IF you can not prove the 25 ohm rule. In my small head, we had 2 ground connection electrodes and since the water pipe to be larger and longer and also tied into a system underground, it was the main grounding electrode and also the single rod included as the supplemental for the 25 ohm rule. I was corrected in human by Michael Johnston that sits ~ above a few CMPs.Of course, me gift me, I had to concern him and also I asked: "So let me acquire this straight. If I have actually a residence that has actually a plastic water key coming in and plastic pipe through out, I need to have 2 ground rods and agree. But, you space telling me that if I have a metallic water pipe the is taken into consideration a grounding electrode, I have to add 2 rods (if ns don"t meter the one) in addition to the water pipe?". His answer was "Yes, the is the intent."I love to learn right native the resource when possible. It do the humbling experience more bearable.
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250.56 Resistance of Rod, Pipe, and also Plate Electrodes.A solitary electrode consisting of a rod, pipe, or plate that does no have a resistance to ground the 25 ohms or less shall beaugmented through one added electrode of any of the types specified by 250.52(A)(4) through (A)(8). Wherein multiple rod,pipe, or plate electrodes are mounted to fulfill the requirements of this section, lock shall not be much less than 1.8 m (6 ft) apart.

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How does one know that the electrode does not have less 보다 25 ohms resistance to ground? The only way to recognize is an expensive three allude test perform by a well-known agency.Requiring a 2nd rod is a knee-jerk reaction come a code section. A ground stick of unknown resistance come ground it s okay augmented with an additional rod due to the fact that there is that possibility that there is much more than 25 ohms resistance come ground. The opportunity of a password violation outcomes in not a tiny bit that effort and expense.This sound a lot prefer a jumper between the hot and cold pipes at the water heater.Well in principle only because we"re talking around a tiny bit the work and not much expense with the jumper.