Ground Rod Ohm Testing - Electrician Talk
2009年5月27日 · When clamped over a ground rod and energized, a CT in the tester induces a test current in the circuit via electromagnetic coupling. The current travels through the soil and returns to the rod (but more significantly the jaws of the tester), thus completing the circuit through all available system grounds.
OHM readings on #4 stranded copper ground wire had high...
2024年8月29日 · Had 540 OHMS of resistance. Shined up the 3/4" copper water line and attached (with the correct clamp) a number 4 copper ground line which I ran into the Square D QO, and to the grounding bar. That worked great. AEMC 3731 grounding tester now says .07 resistance. The only item left is the stranded #4 running outside to grounding rod, reads 25.4 ...
Ground rod resistance - Electrician Talk
2010年9月1日 · There is the "fall of potential" test I've heard about on this forum. I've not used it. Seems like it would take too much time. There is the clamp-on ground tester. I work in a factory and I just drive the rod and then measure from an existing known "Good grounding source" to the new rod. Maybe it's too simple but it's all I got.:thumbsup:
2 ground rods | Page 5 | Electrician Talk
2009年4月29日 · While I was in Iraq working on the bonding and grounding issues we had a ground rod tester to to check ground rod resistance. Worked like a clamp on amp meter. Checked 100's of ground rod and none were even close to 25 ohms. Most were 2-3 ohms, in the sand. Found that interesting.
200 Amp Service # 6 Ground to Ground Rods? | Electrician Talk
2019年4月22日 · It's stupid. NEC says if your ground resistance is too high, drive a second ground rod. It doesn't say keep on going until the resistance is low enough, just drive a second ground rod. And the ground resistance is sort of an arbitrary rule anyway and I'd say 95% of the rods I've tested easily pass (0.5-1.5 ohms is typical).
Stop driving two ground rods, just test the one you have.
2020年12月13日 · If you really want to test this, unhook the ground wire and put a 5a fuse between the ground rod and the hot side of an extension cord. If it pops, it's less than 25 ohms. 10 cent fuse vs $1000 meter.
Ground Rods 101 - Electrician Talk
2017年12月6日 · If you don’t own a tester, don’t know how to test or simply opt to skip testing, you may be out of luck when the power company decides to check your work - resulting in having to redo the entire job of digging a trench and driving the rod. The Nitty Gritty on Ground Rods Ground rods are a fact of life - often overlooked - for many electricians.
Testing Ground Rod Resistance - Electrician Talk
2011年10月23日 · I have had DSA inspectors test my rod installation on a few occasions. They always used the "Biddle Earth Resistance Tester" if it's not 8 ohms or lower, I was told to drive another rod within 6 feet or relocate rod. Then he checks again when I am ready. I found that pre soaking the soil always produces a passed test.
How many ground rods needed? - Electrician Talk
2019年6月24日 · Mike Holt has a video where they simply energized a ground rod and measured current flow with a clamp meter. They also measured ground resistance with a clamp on ground resistance tester. I think it was an AEG. The ground resistance calculated by V/I was pretty close to the measurement from the ground resistance tester.
Choking ground - Electrician Talk
2015年9月10日 · We would use a motor overload tester to pass 50 amps of current from the connection through the ground grid to the ground rod and measure the output voltage of the overload tester. Using ohms law we could calculate the resistance of the ground grid.