Contactless Voltage Detector

When electricity is not properly handled, it results in electrical shocks with a nasty experience; which is why safety must come first when working with electricity or electrical devices. In order to avoid injury, prior to starting work on an electrical box such as an AC mains switch-board or a power supply, you must first verify there is no AC voltage. It is really hard to completely isolate a device from the main supply; so, how can you be sure that there's no voltage remaining?
There are several options available in the market and they range in price, but if you don't want to spend a lot and if you are a true DIY lover, this Non-Contact AC voltage detector is the right choice for you. After watching this video you should be able to make your own AC tester for less than a Dollar.
Track: Defqwop - Awakening [NCS Release]
Music provided by NoCopyrightSounds.
Free Download / Stream: ncs.io/AwakeningYO

[@nenioc187]

Nicely done. Feel the urge to make one myself!

[@CrazyCoupleDIY]

:)

[@Steelplayer59]

Excellent descriptions, graphics, and overall tutorial of the design process in general. With about a half-century of experience, I would like to add a safety suggestion. These types of non-contact devices are great for checking presence or absence of voltage, such as for checking a switch or tripped breaker. However, if you plan to touch conductors, use a proper multimeter or tester designed to actually touch the wires, and test it on a known live circuit beforehand to ensure it works properly. There are some cases where these non-contact devices can read a false negative, where power is really there, but not read by the tester due to other unforeseen electromagnetic influences. This applies to the commercial units as well.

[@CrazyCoupleDIY]

Thanks a lot for your suggestion, it will help everyone who watches the video.

[@samisdamn4062]

never stop please its a request keep making video

[@DW-ft3sd]

That's impressive, but you can buy one for under $20, sometimes even under $10. However, "Because you can" is often something I admire!

[@CrazyCoupleDIY]

So true. But sometimes it’s fun to create everything they way you want, don’t u think so?

[@fatnareda4147]

Genuine, amazing and Intelligent

[@luckyaryan2301]

And bro I like that how till now after 2 years you are seeing comments.big fan

[@CrazyCoupleDIY]

Cheers

[@Mrbeeast297]

Thanks for sharing this video keep it up and stay connected your friend love till the end

[@mining1377]

Good work brother

[@anavigaud7906]

Wowwww great info 👍🏼

[@mmsimmsi5853]

Very well presented, Sir you are great

[@CrazyCoupleDIY]

Well said :)

[@adelaidepeople4810]

Awesome video

[@wojciechg9498]

Awesome man

[@rokiedecentra9656]

hope this helps for those whose circuit LED is stuck in the ON state: for future reference for some weird reason, it only work for me when i have the led to Vcc and the negative of the led on the output of the ne555 pulling it up rather than down..... i checked it on a scope and when the circuit triggered, the output pin connected to ground so when voltage was present it started to flicker as the NE555 tried connecting it to ground, both pins are ground so it turned off. The off time was very short compared to the on time so it seemed like it was flickery but on In the other case where + of led is at Vcc and - of led is at pin 3 of the IC, in no trigger state, the LED is off, when a trigger is there it was connected to ground and the LED was on and flickering. I also saw the intensity was in two states, low and high, in low it was very flickery and dim and when it is very close it becomes very bright and flicker is less also i had the reset pin connected to Vcc as its active low, to ensure the IC is held in ON state rather than reset state, it didnt check it without the reset being connected but it will also help if you face issues

[@yassersaad6725]

Continue doing these and Arduino type of videos. They are really helpfull.

[@CrazyCoupleDIY]

Thanks mate, that motivates me. I have few videos inline. Will be posting them soon

[@adelaidepeople4810]

I agree

[@randhirsingh-pv9yj]

Amazing...... the circuit using IC 555 is more reliable out of the three Circuits as explained by the "Crazy Couple DIY" very professionally.

[@CrazyCoupleDIY]

Thanks a lot mate

[@venkateshks6664]

Thanks a lot for the comparative study, helped me choose the 555.

[@CrazyCoupleDIY]

Cheers thanks

[@venkateshks6664]

@@CrazyCoupleDIY took me about 15 mins to assemble it (555 one) and can certify that to an extent it detects wiring embedded inside walls, well if it isn't dug in too deep.

[@CrazyCoupleDIY]

I do agree to that Thanks for your valuable comment, it will help other users too

[@amiyamondal8957]

Hey venkatesh how much volt did u choose for 4.7 uf capacitor?

[@venkateshks6664]

@@amiyamondal8957 anything over 12 volts will do. I just had a spare 4.7 micro farad and 63V lying about wich I used and it worked fine. the voltage just gives the higher limit for the capacitor beyond which they tend to blow up, and not the lower limit.

[@peceneqMotovlog]

perfect, thank you

[@CrazyCoupleDIY]

Thanks

[@johnmif9808]

very good video and easy to follow

[@CrazyCoupleDIY]

Thanks a lot mate

[@Ramy_Ramz]

Had some components and thought why not, I didnt have a 4.7uf cap, used a 10uf electrlytic cap, was missing 220ohm resistor so used 1k 😅. But it works like a charm (kinda). Very cool concept. Thanks for teaching. P.S. Please post more videos. Really helps A LOT. I am doing my first year of electronics and comms engineering, really frustrating as I have inadequate lecturers. For example your transistor explanation video, never understood the concept of "flow of holes" until I saw your video. The visualisation helps A LOT. That been said. Thank you A LOT.

[@CrazyCoupleDIY]

I am glad that I was able to help you, mate. More videos are on its way, so stay tuned.

[@enriquetortolero]

First... thank you very much for this excellent video, is crystal clear! ...second ... is possible to measure the voltage that you are detecting? I would like to use the first project due to is very sensible, I want to read, show an store the values read by the device, do you think is posible?

[@manoharjethra]

Awesome perfect genius video 👍👍👍👍👌❤️

[@CrazyCoupleDIY]

Thanks a lot mate

[@tanishqbhaiji103]

The last one is is based on capacitive coupling not inductive coupling, larger surface area for the antenna will hugely improve it.

[@hobokaru1350]

where and what kind of antenna would you buy for these projects? (especially the 555 IC one)

[@tanishqbhaiji103]

@@hobokaru1350 you make them using solid copper sire or mettalic foil.

[@hobokaru1350]

also, where would i find those types of pins and the board for the 555 IC

[@itsminer0019]

A lot of thing to learn

[@shiva.chennai]

Super video. Clear explanation. Please upload gold metal detector circuit. Thanks.❤

[@CrazyCoupleDIY]

Thanks I will try mate 👍

[@gartmorn]

The 555 circuit looks like it could be used to check for cables behind plasterboard walls. Will give this circuit a go for sure!

[@CrazyCoupleDIY]

Sure, plz do post your findings in the comment You can also make a comment on my blog diyfactory007.blogspot.com/

[@davemangcucang3719]

thanks very much for sharing

[@CrazyCoupleDIY]

Pleasure 🙏

[@railspony]

Thanks, I'd been wondering why so many people use IC sockets; cheap soldering irons :)

[@CrazyCoupleDIY]

He he

[@Pradeepkumar1960]

Well explained...good.dupet

[@CrazyCoupleDIY]

Thanks

[@watanglipuhadjar2654]

useful 👍

[@AndyChristianLoyola]

nice trick with the 555.

[@CrazyCoupleDIY]

Ha ha ha

[@aminestones5379]

رائع جدا كالعادة شكرا على هذا العمل المتقن.

[@CrazyCoupleDIY]

Thanks 👍

[@ChuckEldridge-hx4vt]

Hello. If I connect the output of the 555IC circuit to the input of a low wattage FM transmitter circuit, will the signal be broadcasted? How does one calculate the voltage drop of the 555 circuit? How would one change the 555 circuit output frequency and duration? Thanks for your very well-presented demonstration and your advice.

[@miknshla]

Can this be adjusted so that only detects when current is flowing? Not just voltage present

[@HammadKhatri]

Great informative

[@krusty1216]

Perfect

[@CrazyCoupleDIY]

Cheers thanks

[@farhadbd7755]

Its good...tnx...boss.

[@CrazyCoupleDIY]

Cheers boss

[@misiriyasalih7095]

I made using transistors. It really works!!

[@CrazyCoupleDIY]

Happy that it worked for you As I said it will work but you may pick up unwanted noise which will give you false positive readings Now if you try the setup I used you will for sure see the difference

[@nagappahbavikatti9065]

Tq sir Usefull your vidio

[@CrazyCoupleDIY]

You are welcome

[@farhadansary9899]

Nice

[@CrazyCoupleDIY]

Thanks

[@crazypeople6760]

Good work

[@anishadak2508]

Does not work

Ok... But what is ac voltage in your location? 127v phase-neutral or 220 volts phase-neutral? Thanks!

[@CrazyCoupleDIY]

220v

@@CrazyCoupleDIY I knew it! Here in São Paulo it's 110 volts and it doesn't work! Thanks for the video and the answer!

[@CrazyCoupleDIY]

Ahh right 👍

[@rokiedecentra9656]

@ it should still work, working distance would be lower

[@francisco9427]

Muito bom 👏👏👏

[@CrazyCoupleDIY]

obrigado

[@mirshanawazali6798]

Very nice and informative..🙂 My question is about the ne555 ic ..can I use pot instead of 1k resistor to adjust the sensitivity of the tester?..

[@CrazyCoupleDIY]

Sure u can

[@joshuamorris2784]

can you specify pot so I know how to do what you doing? how would this work (also dont know what pot is)

[@kaivangandomi7090]

pot instead of 220 resistor? or 10k ? which one is useful for led controlling pls?

[@luckysingh-rb1or]

Please answer one question...if i want to detect 11 kv while standing on ground,will these ckt help,,,the 11 kv wires are approx at 8 -9 meters from the ground level...if no then how to increase the senstivity of this ckt so that I could detect 11 kv voltage while standing at ground level just by raising ckt in my hand safely,,, as it's risky to go near 11 kv

[@CrazyCoupleDIY]

I will not take a chance testing 11KV with this tester mate. Please use some professional and recommended tool for that. This will definitely become an item of suicide

[@riverkirby1937]

I built the 555 circuit and followed the schematic/instructions precisely but the LED stays on constantly. The buzzer works fine however. I've tested it with both 9v battery and 5v (arduino). This is for a school project so it has to work exactly right. Any suggestions?

[@Aristoto]

Hello River can you help out, I have a project on the same title.

[@Mueedwasif]

I made this 3 times but buzzer and light continuously ringing also light flashes no any thing detecting

[@juliusvalentinas]

Does your 555 circuit detect incorect switching power supply connection when there is AC present on the device cover like PC PSU.

[@tanishqbhaiji103]

That is ground not live.

[@rokiedecentra9656]

@@tanishqbhaiji103 that is leakage from the Y capacitor between ground and neutral, if ground isn't connected the neutral will have leakage current onto the ground terminal which is connected to the negative of the DC side as well. This circuit wouldn't be able to detect it in many cases as the voltage will be very low as it is easily loaded down

[@qzorn4440]

very interesting & wonderful circuit. 🥳 Do you have a non-contact circuit to indicate 3 phase [A-B-C] 2,300 volts AC motor rotation sequence? 😎 Thank you. Most 3 phase motor rotation direction "CW or CCW" testers only go to 700vac.

[@CrazyCoupleDIY]

Not at the moment, but I will upload one soon Thanks again

[@cwarrillow]

How thick is the antena wire in the 555 circuit. Thanks

[@stuboyd1194]

Can any of these circuits tell the difference between: 1. A power cord that's plugged into the mains. 2. A power cord that's plugged into the mains and connected to a load?

[@user-ks5tf1xw6q]

Hello, thank you very much. Please explain how to make a good metal detector so that I can make one. I always thank you, engineer.

[@CrazyCoupleDIY]

I will create one video for that in near future Thanks again

[@y0d4]

hi, great project! tell me, can this detect live wire inside walls? tnx.

[@CrazyCoupleDIY]

Yes it does. I have done testing with the 555 and it definitely detects a live wire inside the wall. The one with the transistors can also be used but frankly speaking you need to be really up close to detect anything

[@y0d4]

@@CrazyCoupleDIY then, he need some amplifier? :)

[@stormbytes]

this is nice. Ist here a commercially available module or gizmo that does this?

[@CrazyCoupleDIY]

I am not aware of that mate Sorry

[@rokiedecentra9656]

yes its called a non contact voltage detector...... or a voltage detection pen......

[@electronmath8609]

👍👍

[@machiningroom]

how you can you change the sensibility in the 555 configuration?

[@user-ef6st3hl1z]

Good

[@CrazyCoupleDIY]

Thanks

[@sureshghute2114]

You are really master sent me other videos

[@CrazyCoupleDIY]

Thanks and subscribe for more updates

[@kadhemalhasan3810]

Once I used the IC 555 in an oscillating circuit, when I applied a voltage difference of 9 V, it burned and stopped working. Is a 9 V battery burnt the integrated 555

[@CrazyCoupleDIY]

No it wont. The 555 timer can be used with a supply voltage (Vs) in the range 4.5V to 15V (18V is the absolute maximum).

[@DupczacyBawol]

It shouldn't unless you mistake the + and - poles.

[@hobokaru1350]

What pins and what board (the orange thing with sockets) are you using to put in all the wires and hardware in the 555 IC? Can you detail what brand you are using as well because that would help a lot.

[@CrazyCoupleDIY]

Are you talking about the "perfboard"?

[@hobokaru1350]

@@CrazyCoupleDIY i think so yes, also what pins are you using?

[@CrazyCoupleDIY]

Cool then it's a generic perf-board You can buy them off from aliexpress

[@hobokaru1350]

thank you, but what brand are the pins (the wires) in the 555 IC circuit board?

[@CrazyCoupleDIY]

It's a local one Not branded mate

[@terrysmith128]

I want a temporary indication of the presence of voltage. Buzzer for ten seconds?

[@amiyamondal8957]

Is the ic555 single timer?

[@PhonphanJomjun]

Someone disliked your video I guess that is the same person who dislikes all your videos without watching them. Anyways nice video.

[@kevsconstantino1952]

Hi i just want to ask if this DIY can detect a voltage on motorcycle with a 12v supply voltage? Thanks

[@CrazyCoupleDIY]

Unfortunately not This device can only detect AC

[@CrazyCoupleDIY]

Unfortunately not This device can only detect AC

[@kevsconstantino1952]

Ok thank you so much sir

[@KamenRider82]

Para funcionar o 555 não ligue em fonte. Precisa ser na bateria caso contrário ele fica disparado

[@KamenRider82]

whats minimal voltage?

[@joseluisrojas7412]

in the last test you are using battery of 9v, but in the draw 5 volts?

[@CrazyCoupleDIY]

Yes correct

[@jaybhatt3515]

What is the voltage value of capacitor

[@narayandasshrestha4197]

Can wa use 3volt battery instead of 9 v battery in 555 circuit pls replay

[@CrazyCoupleDIY]

You may but I have tested with 3v and the led stays way too dim

[@naveenchinthakindi7387]

In first project using IC 4017 what is the use of placing 2n2222 transistor

[@CrazyCoupleDIY]

You can remove the transistor if you are driving an led or low current consuming devices. The transistor is basically acting as an amplifier

[@ibrahimhossainet]

I created this project, it is working fine. But sometimes it continues give alarm even if it is removed from the cable. What can I do?

[@CrazyCoupleDIY]

I am not sure mate, looks like it is picking up noise.

[@flatearth2561]

please in which mode this ic 555 timer is working in this circuit and thank you

[@rokiedecentra9656]

monostable, it stays stable low and the trigger pulses make it go high which is not a stable state so it will return to low after trigger pulses are removed

[@iIiWARHEADiIi]

From which distance can this circuit detect three wired cable with good ground line?

[@CrazyCoupleDIY]

None of them will operate if you go way to far.

[@iIiWARHEADiIi]

@@CrazyCoupleDIY cable with ground line none detectable if distance more than 2cm. If it is in a wall,usual depth 1-2cm, it is not possible to find it at all. As result im looking alternatives which will give big detectable distamce

[@flatearth2561]

Can it detector a voltage inside the wall ?

[@CrazyCoupleDIY]

Yes it can

[@lekanthefirst]

You didn't specify how many voltage for the 4.7uF capacitor?

[@CrazyCoupleDIY]

You can put anything higher than 5 volts

[@dharshinipriyarajasekar7963]

Can we use this in water to detect electricity leakage

[@CrazyCoupleDIY]

I have not tried but if you get a success plz do let me know Thanks

[@bukakohler]

What features does the buzzer have? how many volts does it work?

[@CrazyCoupleDIY]

It’s a normal buzzer Nothing special in it

[@DereckGranados]

@@CrazyCoupleDIY a passive one or a Active one

[@rokiedecentra9656]

@@DereckGranados active

[@kalpjoshi2879]

Can I use LM386 instead of 555 with same circuit ?

[@CrazyCoupleDIY]

Lm386 is a opamp 555 is used here as a pulse generator

[@charyrayalavarapu9517]

Can I check the 11 KV line with this. ?

[@CrazyCoupleDIY]

Ha ha ha, if I am you, I would not even go close to that

[@luckyaryan2301]

I like the 555 ic as you like but after some time it is automatically blinking and buger is also working automatically. With out bring a live wire next to it please tell me a solution .

[@CrazyCoupleDIY]

Hi mate I don't have the issue as such so no idea

[@luckyaryan2301]

Ok I think my Capicitor broken

[@luckyaryan2301]

Can I put any different uf Capicitor .

[@luckyaryan2301]

Can I put any different uf Capicitor .

[@CrazyCoupleDIY]

Sure

[@Mueedwasif]

Sir i m using 4.7 uf 50v capacitor and 10k resistor but it beeps continuously

[@CrazyCoupleDIY]

Please check your connections It has always worked for me mate

[@giacomodagostino6554]

I tried ic555 and it burned I followed everything to the letter I do not understand what I wrong

[@rippalmer6296]

Can we use a BC547 for this?

[@CrazyCoupleDIY]

Sure, why not

[@NoorainRazaEC]

Sir can you tell me Why does it happen when i touch my fingers to the antenna , led glows and buzzer beep? (In case of when we use transistors) Plzz tell me sir

[@CrazyCoupleDIY]

That setup is a very flaky setup. Since we are amplifying the signals statics are also picked up and miss interpreted.

[@rokiedecentra9656]

Your body has a capacitance to your house wiring, you will have a voltage on your body which you can measure if you use a high impedance device, when you touch the antenna you are feeding the 555 timer some voltage which is enough to trigger it.

[@rajannarayanan2759]

Explin good

[@CrazyCoupleDIY]

Thanks and welcome

[@vladimirmirkovic44]

Can using different transistor make it detect lower voltages?

[@CrazyCoupleDIY]

Yes u can

[@vladimirmirkovic44]

@@CrazyCoupleDIY thanks mate! What transistor would you use for detecting low voltages like 12vac?

[@athulmartin]

Will it work for Dc current also?

[@CrazyCoupleDIY]

No

[@yadavpk8107]

it will work at which voltage.

[@CrazyCoupleDIY]

Haven’t tested but I think it will

[@mohamadelectro5308]

How many volts should the capacitor ?

[@williamguillen4113]

Over 9 volts.

[@omprakashverma8978]

Where second end of cool is to be connect.

[@CrazyCoupleDIY]

Sorry I did not understand your question

[@patriksajda2032]

can i use any else capacitor?i don't have 4.7uf

[@CrazyCoupleDIY]

May be try 10uf

[@mr.2minutes161]

is it gonna work if i wire the speaker and the led 25 meter away from the amp?

[@CrazyCoupleDIY]

Why would you do that?

[@mr.2minutes161]

@@CrazyCoupleDIY after a power outage in my area, when the power went ON again sometime my circuit breaker is getting jumpscare moment or something, and it turned off the switch, so if im in my room, i would never know if the power is up, and i just wanna know when my power went out, its from my breaker or the whole area.

[@mr.2minutes161]

@@CrazyCoupleDIY im gonna hook it on the cable before the breaker.

[@CrazyCoupleDIY]

@@mr.2minutes161 Ahh, that makes sense. But frankly speaking, it won't work 25 M is a long distance and the current will drop. May be add a NodeMCU to send the signal off to a receiver or a webserver or something

[@mr.2minutes161]

@@CrazyCoupleDIY i guess i'll do that if theres no cheap alt, im looking for cheapest and easiest way possible if i can, since nodemcu and battery price can fed me for a day here,

[@bigboxthailand5732]

can i check 12v dc voltage's wire?

[@CrazyCoupleDIY]

I did mention in this tutorial that this tester detects the alternating current and produces the tone. So unless u have an alternating current you may not be able to hear the tone going up and down.

[@mihaithemystic2890]

can i use one of this? NE555PWR, NE555P, NE555D? i can't find NE555N.

[@CrazyCoupleDIY]

The 555 ic is used to generate pulse So any one of them technically should work

[@indianism3191]

Could you please share the 555pin numbers along?

[@CrazyCoupleDIY]

Please check from 3:23 or have a look at my blog for full details

[@lieza001]

i wonder if this account owner is actually sir tarantula3

[@CrazyCoupleDIY]

Why do u think so mate

[@francisco9427]

Funciona com pilha de 3v?

[@CrazyCoupleDIY]

mas não tão eficazmente

[@kunduneeraj1989]

can this voltage detecter high voltage detect?

[@CrazyCoupleDIY]

It will but I won’t recommend

[@majdsaad622]

This can only detect AC voltage , can it detect DC volatge?

[@CrazyCoupleDIY]

No Basically this is a current detector It detects the alternating current

[@vadesines5023]

4.7 uf capacitor volt's?

[@CrazyCoupleDIY]

The circuit can only handle a Max voltage of 15v, so anything higher than that will be fine

[@jasontatum7277]

hi can we use this circuit in an 8kV AC supply?

[@CrazyCoupleDIY]

Hi there I have not tested it on 8kv so I may not be able to give u an affirmative answer

[@jasontatum7277]

@@CrazyCoupleDIY hi sir. what do you think? will the circuit won't be affected by the 8kV induction?

[@CrazyCoupleDIY]

The circuit depends on how much magnetic flux is transmitted and received. Depending upon the flux a current is induced in the coil. Now if you pump in a massive amount of current and the pin of the ic is not able to handle that amount of current, the circuit will blow off. (Can cause injuries).

[@rokiedecentra9656]

if you are using a 555 timer to detect 8kV AC..... then what are you doing..... there are better products with proper safety certification which you should be using,......