How would you replicate the water tray experiment in the real world, say an outdoors cable has snagged and ends up surround by moisture collected in the conduit. Would you stick the ground probe on a nearby ground terminal of straight into the soil? Would you then expect to get way less than 5.5 GOhm?
Connect it to the conduit, if metal and then one of the cable leads. Or the ground lead in the cable run, or between the neutral and line with the devices disconnected. Anything less than 2M Ohm may cause problems. Anything much lower than that will cause problems.
You test the meter is working correctly by pressing the test button test leads apart you should get a zero reading short the lead together press test you should get full scale deflection. This tells you the meter is working correctly .
@@AnotherMaker those UNI-T test are fantastic for learners and apprentices. Just starting out . Once they have experience they can upgrade to one of the big brands like fluke
Are these not common for electricians to use in the US when she went installation certificate? Certify? It’s good or not? Because the way these comments are peoples seem to think it’s revolutionary to check an electrical installation is safe
@@AnotherMaker This will be the right experiment. One electrode (positive) is connected to the metal part of the tool and the second electrode (negative) is connected to a container of water. Immerse the insulated handles of the tool into the water and measure the resistance. If there is damage (cracks) in the insulation, then the megohmmeter will show low resistance. This is a fairly accurate way. Naturally, be careful when working with high voltage. Good Luck,sincerely.
An ignition circuit on your car produces between 30-40KV. It’s annoying when you’re zapped by one, but not that bad. A zap from static electricity is usually around 5KV. It’s not the voltage that does the damage. It’s current.
I don't understand the difference in the "Multiple points of failure" test. Both multimeter and insulation tester detect continuity. What is the difference?
it is possible that a "normal" continuity test will tell you if something is shorted because it doesn't have enough current or a high enough voltage to detect the short.
Your multimeter tests continuity with a few volts and pretty much no current which won't reveal any issues you might experience under actual live conditions (where your voltage might be anything from 110V up to 400V depending on your country and grid).
The uni-t 501 reads megger ohms on the 250v and 500v range , not gig ohms, the minimum acceptable value for insulation resistance is >1 magohm ie greater than 1 Megohm the maximum that tester can display is ol = over limit or l = over limit ie full scale deflection. On new installations we expect to see full scale deflection .
dont know how you are supposed to test isolation in your country, but in france, isolation tests are never done between live and neutral wires. Tests are only done between neutral and earth, live and earth and finally between live wires in industrial electrical setup.
@@AnotherMaker in "real world" you have terminal components plugged between live and neutral (computer, light bulb...). it's not advisable to inject 500+vdc even with low current. Only revelent test that should be done between live and neutral is a short circuit test with ohm multimeter.
@@AnotherMaker Well I'm not fully sure how they function, my fear is that a megger made for more robust wires, 230V AC here in Europe maybe would damage wires in the 12V system?
I testing diesel (piezo, etc ) injectors in automotive diagnostics because specially with misfire and if u use multimeter resistance is ok but when I use this 501 insulation tester LOL shorted not fully injector .@@MaN2Mega