How to Turn Off Ghost Voltages with Dual Impedance (LoZ) Meters

[@kristiandawe85]

I thought about buying a fluke 77, but this meter has more than enough for my electrical needs, I have the 117 and love it

[@SparkyChannel]

I agree!

[@edlopz1722]

Bill, I enjoy every single video you put out there. Tons of good and helpful videos. I hit the “Like” button right away . This is one of my favorite channels. Thank you !!

[@SparkyChannel]

I appreciate that! Thanks so much! New video today: How To Wire 3-Way Switches with Diagrams Included: kzbin.info/www/bejne/qpy6maSDj86BrNU

[@89DrFunk]

Thank you so much for the clear examples and explanation. I watched 3 videos which was too vague me but you was clear with the examples. Thanks.

[@SparkyChannel]

Great to hear! Thanks!

[@math020]

Hi iam a new electricien I was wondering if you can guide me on witch multimeter and ampmeter to buy I prefer to buy the right one right away I was looking at the klein cl800 or fluke 376 for the ampmeter And the klein mm700 or the fluke iam not sure witch modele so many on the market Thanks for your help i always what your video Great job

[@electropentatonic]

In 277v multiwire branch circuits I'll get strong ghost voltage on dead circuits if they share a pathway. Just picked up this meter, looks cool. I'll also pick up 120v on open neutral circuits if the open neutral still has a good length of wire. Sometimes it takes a dummy load or continuity test to ground to see the neutral isn't actually there. This may be helpful

[@mathman0101]

This effect is called an Electric field coupling (also called capacitive coupling). It occurs when energy is coupled from one circuit to another through an electric field. This is most likely to happen when the impedance of the source circuit is high. The most common places to encounter ghost voltages are blown fuses in distribution panels, unused cable runs or electrical wiring in existing conduit, open ground or neutral on a 120 V branch circuit or in card cages where 120 V control circuits are used to control assembly line or conveyor functions. When new buildings and factories are built and wired, it’s very common for electricians to pull extra wire through the conduit for future use. These wires are typically left unconnected until needed, but are subject to capacitive coupling thereby creating a potential for a ghost voltage measurement. Which takes me onto an even more interesting topic the safety of electrical wiring and electrical products due to the creation of electrical fields but more typically magnetic fields in modern homes and whether they create a potential health hazard. That creates an important issue of what testers we can use to address this and the importance of shielding from stray radiation.

[@SparkyChannel]

Thanks Math Man!

[@buseini]

Electric field coupling is known to damage VFD's. It will also damage the equipment i.e motors etc that are connected to the vfd.

[@MrTooTechnical]

Great vid. What brand of car battery did u use to make the ghost voltage??

[@wim0104]

one of those huge cylindrical ones on a pole, like a Z size ;-)

[@wim0104]

but seriously: when conductors run parallel, they induce electrical current & AC voltage in each other. that's one reason why there's guidelines/code about bundling circuits together.

[@SparkyChannel]

LOL! Yes, bundling wires can cause radio interferance as well.

[@davidlindh7938]

It’s using the moisture in the wood to the ground in the other box for a return. Going to loZ creates a 3k ohm resistance.

[@wattsup918]

Agreed. Ghost voltages are due to capacitive coupling in the wiring. Assuming the meter hi-z is 1 megohm, you need only 3 nanofards of capacitance to have 11 volts at the meter. I wonder what the capacitance of 14/2 per foot actually is...

[@wim0104]

So who is this low-Z/LoZ measuring most useful for: shouldn't electricians be able to cope, and work, with ghost signals or voltages?

[@wim0104]

in this example, the regular voltage measurement proves that the metal box is not grounded properly. What is loZ doing that's useful?

[@SparkyChannel]

LoZ provides a measurement of what is wanted without dealing with confusing "ghost" voltages.

[@TheGregWallace]

Question.....I watched your video on "How to wire a half hot receptacle with power to the receptacle". I have two switched receptacles in my house like the set up in that video... one of them is the receptacle under the kitchen sink (the switched portion is for the disposal and the other half is for the dishwasher) the other switched receptacle is in a formal living room to control a lamp. My question is, I used my fluke 337 True RMS clamp meter to test the voltage in the switched portion of both of these outlets with the switch off and was getting a reading of 4 to 5 ac volts, is this normal? I'm assuming so because of the research I have done so far. We have lived in this house for 17 years and never had a problem with these outlets and everything works like it should. I have not changed out these outlets or done anything to them, the reading of 4 to 5 ac volts is what the receptacles show when off. Any info you could provide would be greatly appreciated Sparky. Thank you for your time.

[@oakstreetanimals3474]

yes. a meter with a low z setting would show 0 volts.

[@TheGregWallace]

@@oakstreetanimals3474 Thank you.

[@notme22]

Does the CL450 do DC Low resistance?

[@greenled5]

I'm trying to understand how the normal voltage setting on the multimeter is a high-impedance setting. It seems like that would be a zero impedance setting since it does not affect ghost voltage

[@chriswarda6114]

Hello, can you please review the Fluke 117 600v Digital Multimeter and let me know.

[@shuyanzhao8824]

I understand ghost voltage but I don’t get how Low z is useful? Since you use low Z and you had 0V between a know hot conductor(120V) and a open circuit element. If you don’t know one of them is hot you could get shock

[@wim0104]

so the voltage here is NOT an induced voltage, nor is it ghosting; the breaker is on, right? sometimes ghosting is caused by damaged insulation, i.e. voltage leak. Any other cases?

[@SparkyChannel]

Yes, it can be just normal electrical field interaction. For instance on standard V setting, a light coming closer to your meter can cause a fluctuation in the reading. LoV setting just gives you the reading you want in most cases.

[@wim0104]

finally watched this video properly: this case with a low voltage drop from "120Vac live wire" to "not grounded" is nothing to do with ghosting. This is plain old "missing ground". I don't see how LoZ is actually helping here? Same with "open neutral".

[@Scrollermania1963]

@@wim0104 Hopefully this fluke article will help clarify... www.fluke.com/en-us/learn/blog/digital-multimeters/dual-impedance-digital-multimeters

[@grantsdad177]

I’m looking to get a fluke meter I’ll either be getting the 116/323 kit or 117/323 kit I won’t use the volt alert on the 117 and I hear the temp on the 116 isn’t very accurate so those two features cancel out so I’m left with what’s more important micro amps or amps it will mostly be used for home diy but I like to buy good tools in case I get into a trade

[@michaelperez9290]

I have the same meter. Awesome vid Bill!

[@SparkyChannel]

The 117 is an awesome meter! :)

[@thegoldenland]

I still don't understand what the LowZ setting is for. What is the purpose of reading LowZ. voltage?

[@thegrave2000]

To be really sure if a circuit is energized.

[@urkkan]

Like the old Wiggy, although not as fancy as the Fluke 117, but it does the same with its low impedance of 4000 ohm!😊👍

[@SparkyChannel]

Yes, I love my old Wiggy! ⚡️⚡️⚡️🔌💡

[@garydudgeon]

Good video Sparky. Good topic and good meter. Thanks for great comment.

[@SparkyChannel]

Thanks so much Gary!

[@konstantinusstoyanov9749]

Your videos always have a great content

[@SparkyChannel]

Thanks so much! ⚡️⚡️⚡️🔌💡

[@MihaiDobrin88]

can you make a video to explain vfd mode on a multimeter thanks

[@chrisfyfe4047]

Good one , I carry a 117 , and a T6 1000 .

[@SparkyChannel]

Right on!

[@Eddy63]

Good demo and Fluke products ...

[@SparkyChannel]

Thanks Eddy!

[@farmerdave7965]

My wiggy has automatic Low Z. When I troubleshoot control panels that have triacs and SSRs I like to use my low impedance test light.

[@SparkyChannel]

Automatic Low Z is the bomb!

[@erikyoung256]

Thanks for your explanation. Very handy!

[@SparkyChannel]

Glad it was helpful!

[@IliyaOsnovikov]

Does anyone know what electronic components are used to make that "LoZ"?

[@Persojet]

Smaller resistor

[@optimusvader7823]

This is great , I got this meter few days ago.

[@SparkyChannel]

Nice choice! :)

[@optimusvader7823]

Sparky Channel THANK YOU ⚡️. I Being using FLUKE meters for about 15 Years and they are great . Like I said i just got a New Fluke 117 and Also a FLUKE 376 FC ( Clamp meter and comes with a iFlex i2500-18 to go up to 2,500 Amps ) . I Still have my first fluke meter ( FLUKE 75 ) and also the one that I replaced ( Fluke 23 series 3) . With Fluke you get what you pay . ⚡️⚡️⚡️🔌💡.

[@SparkyChannel]

@@optimusvader7823 ⚡️⚡️⚡️🔌💡!!!

[@illestofdemall13]

It can be dangerous to only use one form of testing. Sometimes you can have a bad neutral and a bad ground, and the meter won't show 120 Volts. This is why I also use a pen tester in conjunction with a meter.

[@SparkyChannel]

Excellent advise, thanks!

[@illestofdemall13]

@@SparkyChannel No problem.

[@SparkyChannel]

@@illestofdemall13 ⚡️⚡️⚡️🔌💡

[@illestofdemall13]

@@SparkyChannel Using the pen tester can also indicate if there is voltage present on the ground wire, metal chassis of equipment, and/or metal junction box that shouldn't be there under normal conditions.

[@darrylm3627]

😀👍🏿Good Stuff,GreatTips

[@nasser.ghandour]

Thank you

[@jackie9350]

Keep it up sir!

[@SparkyChannel]

Will do, thanks Jessie!

[@peterfong8777]

Thanks 🙏

[@SparkyChannel]

You’re welcome 😊

[@bowlampar]

It is showing 0 'DC' volt, not Ac

[@Todestelzer]

I used LowZ after a couple smd resistors on 230v and blow them up this way. You have to watch out what you’re doing 😂

[@SparkyChannel]

Thanks for the tip.

[@hugos31]

fluke 117 Good

[@CNCTinker]

it is not a ghost voltage, it is induced voltage from the ac, you call it ghost and it sounds like some magic stuff

[@mikeadler434]

👍👍

[@SparkyChannel]

Thanks Mike!

[@ИгорьПетренко-ж4р]

Очень хорошо объясняете я так думаю, но если бы это было на нашем языке, или хотя бы с русскими субтитрами то цены бы не было этому ролику.

[@asadbabilbabil7791]

N .is not zero... be carful

[@SparkyChannel]

Thanks!

[@tommycho9068]

Thank you.