How to test a bridge rectifier with a multi-meter

[@chirots]

As Amateur, I did learn basic electronic lessons in high school and first year electrical engineering(I went to Chemical Engineering), I once in a while repair my own stuffs. I often visit your channel to refresh my memory. Thank you.

[@indioflechudo6221]

his is the first video, that I found , that explained how this components are tested. without any confusion. Thank You. Best Regards

[@jimmyfriend532]

I'm still here for ya Paul, Glad you are feeling better,

[@kenlanier2131]

I have watched your videos for awhile mostly because of my interest in hobby electronics and amateur radio, trying to get a better understanding of electronic theory. It finally motivated me to go back to college to pursue a degree in Computer Engineering. I am currently taking good ole ELN131 :) Got to start somewhere. Thanks again for the videos and the motivation. -Ken KN4ROL

[@keithking1985]

Ken whats ELN131?????

[@kenlanier2131]

@@keithking1985 Keith, E:N131 Is an entry level electronics course at college Analog Electronics.

[@keithking1985]

​@@kenlanier2131 Im going doing the same thing!! back to education as soon as i get my dad sorted out, he had a mild stroke recently. thank God he wasn't effected physically, but iv noticed that he's sleeping alot more, and his memory hasn't been the same.. but he knows now to start slowing down a bit now, he's 74 & was still going up & down ladders running around over doing it.. it was coming in a while now , just thank God he wasn't left really bad off. don't know why im tellin ya this.. but anyway i cant wait to get back learning something that i actually love doing... (even the boring theory i love)

[@kenlanier2131]

@@keithking1985 I wish your Dad the best! If your like me you will really enjoy going back to school. It was awkward for me at first, I am about to turn 50 this year and I have worked 25 years in IT as a Network Administrator but was laid off after a acquisition, so that has actually given me the opportunity to go back and finish something I should have along time ago. I am excited. Hope the best for Keith. Keep me posted.

[@keithking1985]

​@@kenlanier2131 i will do Ken keep ya posted im always on Paul's site here. he's a cool guy!! im 40 about to turn 41 in a few months, iv gone back to education before 10 years ago doing sound engineering but done nothing with it. but loved learning ya know!! I feel like iv been handed this gift!! not to say im gifted at this at all, but this gift as in a passion in me for something in particular.. never stayed in any job coz i just got bored,, made most my money making art and shight and selling it. table's mirrors outa wood slate and carvings etc... but that was just for cash in me pocket, ya know!! i honestly thought i was going to go through the rest of my life not been passionate about nothing.. heavy shit for the mind to put up with. but just outa nowhere i saw a video on how a joule thief works and was mind blown.. mind just blow out all over the wall's.. i knew there & then what it is that im going to do with time i have left, which now i hope is as long as possible where before i couldn't give shight about.. no bullshit electronics saved my life....FACT!!

[@tdauthantic]

greetings from Bharat - INDIA , GREAT VIDEO learned accurately , thanks for ever

[@zhuzzir]

Thats gold, rmembering "all diodes (in a fbr) points (schematically) to the + sign..." and thats folks is the key in understanding this tutorial on how to test bridged rectifiers - still its not gonna hurt to keep or bookmarked this vid for "leisure" refreshment every now n then! 😁 Gosh how did I missed that the 1st time (and every ones afterwards) I watches this vid 2 yrs ago! Of which if I do, wont be needing me coming back here for this "refreshment" tutorial (again, and again, 😓).

[@keithking1985]

just noticed how you appreciated the new marker!! judging by the shape it should feel nice in the hand.. little things like that bring a smile to my face.. i hope ya know you just gave away a super heroes secrets there.... Electro-Boom! isn't going to be happy with ya Paul!!! If he comes for ya just throw a bucket of water over him... YA'll BE GRAND!!!!!

[@gillesgonthier4976]

Excellent video, thanks. Question: Could you test the bridge rectifier in circuit?

[@MiloPerrotti]

yes

[@mohdfaizal275]

Yes I guess. Mine shows 0.5 voltage drop across plus and minus when tested in circuit. Off circuit reads correctly which is 1 volt voltage drop.

[@jdbrcs]

I also get a drop across the + to both AC pins. applying Neg Lead to + on rectifier.

[@MalagasOnFire]

I have a beefier one for mains circiut developing / testing and It is checked . Quite handy before they get into higher voltages.

[@abyssalsoul6216]

Thank you for this. I am testing the bridge rectifier in circuit. The first 4 steps check ok but when I do the last step I do not get the doubling of the voltage. I get the voltage drop of only .5v and not 1v. Does that mean the rectifier is bad? Anyone?

[@paul.alarner6410]

good question as i get this too!

[@j.m.5995]

What if you check the resistance be the two AC leads and the result is 1.5 ohms. Would that be the reason my compressor keeps blowing fuses

[@darrylparrish6805]

Hello , I found your video very helpful . My questions are , how do you understand the information printed on the front of the bridge rectifier , and how you tested it in circuit. Thanks

[@safijab2102]

What if in step 5. I didn t get V drop *2 , I get value V drop equal measured in prevoius steps?

[@tanner1985]

I ask the same.

[@davidobrien-monk9156]

Then you have a failed diode! Unfortunately the method of testing is incomplete as not every individual diode (there are four of them) has been individually tested. 1) Lets label the pins as A, B, C, D, where A is plus and D is minus, B is alternating current and C is alternating current. 2) Test in each polarity direction:- A to B, B to A, B to D. D to B, C to D, D to C, A to C, C to A,

[@philipchong3098]

Hi, I have the same problem. In the end did you find out whether you have a good or bad rectifier?

[@surgingcircuits6955]

I think I have a good video suggestion. Interested? AC motor running driven by a bridge rectifier without filter caps. If yes, let me know.

[@quocdai79]

Do we need to remove the bridge rectifier from PCB to test it ?

[@MiloPerrotti]

no

[@brianmcdufford1]

can you test the bridge rectifier that is on a circuit board?

[@jamesallen6007]

As always, simply put and easy to follow.

[@JG-ot2zf]

Hello I have a GBU406 and it test ok exept that between the DC + and -- the value stay's at .5 not .5+.5 why? Is the rectifier defective also it has 170vdv when the power is on. It is for a 24 vdc battery charger for a weelchair. Thank you

[@deanodley]

Very well explained and simple to understand - helped me to diagnose a faulty 3n257. Thanks.

[@Music-Gear]

Great video, When testing my bridge diode, I don’t get a doubling in voltage with the multimeter. When testing the middle legs, I get a 0.560 v, but when I test the minus and positive I don’t get doubling but 0.740 v but an increase of around 0.200 Is this diode any good

[@tnisius1]

I don't think you've fully recovered.. I believe you only tested 2 of the diodes in the bridge. Try using the schematic to show your connections and explain what is being tested and I think it will show that only one of the diodes from each ac input was tested.

[@kenlanier2131]

Tom I am a newbie to electronics, but being the diodes are sealed in a package the only test points would be what you can physically get to on the leads. Please correct me if I am wrong. -Ken

[@tnisius1]

@@kenlanier2131 Since there are 4 diodes in the bridge, it would take 4 tests to test each of the four diodes. Looking at the schematic of the bridge, note that each diode is connected between two terminals of the bridge. Connecting the meter across each of the four diodes is required for a complete test of the bridge rectifier. Each of the four tests below should show about 0.6V: 1. Connect the negative test lead to the + terminal of the bridge and test to one ac terminal. 2. Connect the negative test lead to the + terminal of the bridge and test to the other ac terminal. 3. Connect the positive test lead to the - terminal of the bridge and test to one ac terminal. 4. Connect the positive test lead to the -terminal of the bridge and test to the other ac terminal. 5. Repeat the four tests above using the opposite polarity of the meter and you should read an "open loop" for each diode. -Tom

[@gottogosome]

Right. His last test between the + and - isn't necessary

[@sydneybarnard8569]

You are correct sir, one test really missing. The test between the two AC input points should give no reading either direction. If it does one of the diodes are blown.

[@brutusjb3814]

​@@sydneybarnard8569 should it say OL, or will it indicate with a buzzer and flash red like mine does

[@consolenichecsn6930]

4:37 What if you get lesser than 1volt (0.6v) when you measure across the diodes in series but each individual diode measures at around 0.55

[@alveramps]

Thanks for the video, I have a question. I did the test and it measures 0.45 approximately between ac and rectifier but when I go accross the entire rectifier it measures 0.57. It should be around 0.9 right? So, what does this mean? Is it bad??

[@televisionandcheese]

I have this too, and for a splitsecond the meter beeps when I touch them, before going to about 550

[@philipchong3098]

Hi, I have the same problem. In the end did you find out whether you have good or bad rectifier?

[@alveramps]

@@philipchong3098 yes bro, I decided to swap the bridge rectifier for a new one and problem solved!!!

[@Falcon-cd9uu]

Hi Sir, thanks for sharing your knowledge here. I'm a newbie here in the Philippines AL DONAIRE. God Bless You Sir.

[@vwaudiwelder]

Thanks so much for the explanation. I have a Chinese compact plasma cutter and this this is what exploded on the main PCB. I am unsure if I can use a 3A/1,000W instead of a 2A/600W that was there previously?

[@keeganharmon8595]

Yes u can do so without any worries. If it were the other way around then you certainly would not want to do so. Remember, it is almost always best to over-rate rather than under-rate components

[@patkelley8293]

That is exactly what I needed to know. Excellent and clearly explained. Thanks!

[@learnelectronics]

You are welcome!

[@davidcommander8849]

To those asking if you need to pull the component off the board: yes, you may. I was getting readings showing voltage drop in the negative bias direction and when I removed the BR from the board and retested it was fine --disappointingly.

[@broken6914]

Learned something. Just one question. What if on step 5, diode voltage drop was not doubled?

[@GunterCantGame]

This is what mine was doing too, step 5 gave me a the same drop as the other steps so I'm guessing mine is bad

[@tanner1985]

@@GunterCantGame Actually I have an Induction Cooker blown , TWO bridge rectifiers give step 5 the same voltage drop not doubled. Are they BOTH blown, and that's the cause?

[@philipchong3098]

Hi, I have the same problem. In the end did you find out whether you have a good or bad rectifier?

[@xdctech1856]

this is very clear tutorial for electronic guide please make more videos on each electronic components on how to test.

[@JahanZeb1976]

Wonderful video as always. Great to watch any upload from you dear sir.

[@akdiscreto]

Hello, If I measure the option 5, I do not get a double drop ( 1 V) but the ordinary 0.5 V DC. Is it an indication of a fault?

[@ilijadadasovic6962]

Thank you for this basic tutorial, but have question, if this BR (bridge rectifier) show voltage drop, is that mean that is in good condition or need to be replaced?

[@Falcon-cd9uu]

I am one of your subscriber here in the Philippines. Thanks again Sir, God Bless.

[@BrucesWorldofStuff]

Glad you are feeling better! Yes it is the little things in life, like a new RED Marker... :-) Thanks Paul... LLAP

[@mrfixer6047]

In my case rectifier in a monitor smps has 0.5v drop on each side and 0.5v drop in dc output instead of 1v. What do think? I do the test on offline pcb.

[@mustafaasefe6404]

Thanks sir for the video. It is very useful, excuse me sir I am beginner in electronic maintains can you give me an advice to how I start electronic maintains ?

[@leabluis9182]

Thanks very clear. excelent . Good instructor

[@vagautohaus4492]

subscribed, the easiest and quickest method i could find - do you have any videos for testing SF20A300HPI (i think its a mosfet or dual rectifier but has 3 pins) and a FSCQ1565RT Fairchild Power Switch and an Optocoupler? l love the way you deliver the knowledge, so easy to absorb

[@JohnJano]

This helped me out majorly! My M4C-3 tested perfectly! :) Thanks so much for this!

[@alchemy1]

It is sort of confusing. When testing a diode, you put the negative lead of the meter to the arrow side of the diode to measure voltage and the positive on the tail end. But as a rectifier, the arrow head end represent positive side of the load, however to measure it on the meter you have to hook up the negative lead of the meter to it. And also, you hook up the positive side of the electrolyte capacitor I assume if you want to remove ripples. Is this correct? So, to test the rectifier with a meter, you hook up the positive to the negative side of the rectifier. Hmmm I can see why it needs closer attention as to why the rectifier is labled differently. The arrowhead is positive side with respect to the load and so it labeled with respect to the load and not the meter.

[@paul.alarner6410]

whats it mean if i get no drop in step 5 but only .5v with the leads reversed?

[@firstlast8252]

I'm excited you like your new red markers. it looks great. I was wondering when you were going to break those out. also the other item I ordered for you is coming from India I think that's why it's taking so long. Should be at your place between Jan 27th - Feb 14th. Thanks you David from greeley Colorado

[@learnelectronics]

Thank you David! There was no info in the package who they came from. I really appreciate your support.

[@tahseendar1917]

How to test MOSFET and transistor

[@timhorton95]

if i get a reading on the other direction ?

[@jordanengland8163]

Well done. I'm subscribed. Can't wait to see more and go back through your vids. You are making a difference in my learning.

[@MirsadIsmani]

Best video ever thanks for the explanation

[@aaroncarter8845]

Looks like my bridge rectifier is buggered, cheers mate!

[@marcb8934]

I have two B20XB80 bridge rectifiers rated 800V at 20A and one reads higher drop than the other. Would it be worth replacing both?

[@VideoServicesLI]

Totally confused. I used this test(DC) method and it showed my rectifier as dead, zero voltage either way. I did a diode test and that showed my rectifier as good. So how do I know which is the right way? I do not have a scope.

[@Matt-rq6wz]

I know very little. If you measure a rectifier on board will you still see the same numbers? I suspect it must be removed from the board to test in this way?

[@learnelectronics]

You need to measure it with a load, so you can leave it attached. You want to disconnect things like resistors, caps, inductors etc. they can be influenced by other resistors, caps and inductors in the circuit. However, you only need to resolder 1 leg.

[@Matt-rq6wz]

@@learnelectronics thank you! If a thermistor burned up would you first look at a rectifier for failure on a power supply?

[@WernerVanAswegen]

Thank you. Just what I was looking for.

[@RapidBoss08]

Your voice is so soothing

[@PT-ElangoChakravarthyD]

Very good teaching thank you sir I like to learn more

[@RespawnRestricted]

Just got a 5 pack from AliExpress today now I can quickly test them

[@mirceanicolaepop3707]

Good health to you!

[@goober650NX]

Clear and concise explanation. 👍👍

[@TaaRiiFrp]

you are great teacher mate.

[@MikeyMack303]

Great explanation! Thank you very much!

[@mdmazbahuddin5592]

hi, can you recommend me full bridge rectifier with below 0.3V forward voltage

[@benedictnyondo2737]

what if + and- no voltage

[@pvanb2]

what about ac pin to ac pin ?

[@albertmanayon4552]

the one you test is a good diod?

[@RobBzReef]

This was really well done thank you

[@MujazAdventures]

I've learned a lot from your videos. Thanks and more power.

[@ilnil]

Thank you very much. neatly explained.

[@babarfarid1495]

How to test a transistor sir?

[@thepreviewchannel6398]

I got .3 volts is it good?

[@rodeljrpacinos4369]

Thank you for accurate explanation. Keep it up

[@Sopanewyork]

Good job dude. Great explanation.

[@gamefahad]

very simple to understand 😊

[@danielmeecham464]

Tremendously helpful! Thank you sir!

[@headway19]

Excellent explaination Sir 👍

[@seyyedrezahosseini2349]

Thanks a lot for your guidance

[@cdavid4insurance]

Nice one. This is clear

[@MCsCreations]

Pretty interesting, dude! Thanks! 😃

[@nathangideon9638]

I like that, thanks for sharing your knowledge

[@YouAllKnowBob]

Does this work with wooden bridges and steel bridges or just silicon bridges?🤔(😋) Good video! 👍👍

[@Electronzap]

Ha!

[@subhan1641]

i got a GBP410 ,is it all similar ?

[@learnelectronics]

Yes

[@subhan1641]

@@learnelectronics i need make this ,by using some diodes ,i saw on other videos they make it soldering 4 of it,.but i dont know which diode to buy,i need to make 4 amps ,700-1000v ,.

[@ArceAngel]

very informative! thanks..thumbs up all the way!!!

[@cobar5342]

Thanks for a great video

[@tahseendar1917]

Never seen such an explanation

[@hslahiri2396]

Excellent & easy to understand clarification ... great liked it a lot .. Hence a big Thanks .. subscribed too

[@michaelpadovani9566]

Amazing how much you can do with a multimeter when you know what you're doing

[@ABID5]

*FULL BRIDGE RECTIFIAAA!!*

[@benbaselet2026]

M.A.F.B.R! kzbin.info/www/bejne/ene0eGyhqr2Grsk

[@rolandoperez25]

Thnx for the knowledge

[@ApolosaCakau]

Thank you for the video, very helpful, Subbed!

[@khandakermushfiqurrahman8501]

Thanks a lot Sir.

[@wclugston]

You definitely sound better!

[@benmuetsch]

Great tutorial, thanks a lot. :)

[@davidhomboura9189]

Cool tutorial

[@pulesjet]

I need another pair of diodes for my Wind Turbine. Three Phase PMA. Permanent Magnet Alternator.

[@riyadm5984]

Thanks is very helpful 👍

[@treadmilltech7119]

Exillent explanation 👌👍👍👍👍

[@naderhumood]

Good test method....

[@michaelogden5958]

Thank you!

[@RixtronixLAB]

Creative video, thanks :)

[@turkalpkucur]

thank you

[@mohan4949]

Super idea.. Tq boss

[@durgasherya3531]

Very nice