Your video just saved me the cost of buying a new Microwave with the ongoing 300% inflation rate in my country, though I fried my new NCV ampere Meter in the process beyond repair (to no fault of yours) I made the mistake of wanting to know the transformer output voltage to the magnetron under load😂 before finding your video. The continuity test position for the capacitor was the magic wand in my case. Replaced and the microwave is now alive after I lost hope in it before.
Thanks for the info.You are on point,I am currently struggling with fixing one after electricity supply company supplied use with 420V instead of 230V.The microwave oven is quite and no display.Now I know exactly where to test.👍👍
Thank you for the video. You omitted something of extreme importance. You may have discharged the capacitor before handling it, but you did not show how to do that. People watching your video may not know that capacitors hold a charge and can hurt you badly. You can't always be sure they have been discharged by the circuitry in the microwave after unplugging it. Also, the new capacitor should also be discharged, just in case someone had bought it, used it briefly, and returned it to the store.
A good way to test your capacitor .... is to wire it in series with a 25 Watt , 230 Volt ( UK ) Tungsten filament light bulb and connect the whole lot across your ( 230 Volt , UK ) mains .... the bulb should glow dull orange ( similar to a 1940's tube ( valve ) radio ! ! ) ... your 1 μF capacitor is OK ( and .. YOU ! have made an everlasting night light ! ) .. DAVE™🛑
Like other youtubers who have made videos on this issue, you have missed the main point. You have proved that your component has 10 megohms of series resistance, but that doesn't prove that it functions as a capacitor. The RC time constant of that capacitor is 1 ufd x 10 MOhm = 10 seconds. That sets the charging rate. In fact, your ohmmeter only built up to the final value slowly, with a time constant that looked like about 10 seconds. That's the observation that proves that the capacitor is functioning properly. If the resistance read 10 MOhm instantly, that would have been evidence of a fault.
@@abetm2193 9.2 MOhm is fine. Two points: (1) resistors used in this kind of application are typically +- 10% or worse. (2) The purpose of this resistor is to make sure that the capacitor discharges by itself once the charging voltage is removed. If the resistance is 10 MOhm, then it takes a few times 10 seconds to discharge. If it's 5 MOhm, then it takes a few times 5 seconds to discharge. That's OK, too. The problems start when (a) the resistance is very low, in which case the capacitor doesn't even charge up - and could even be shorted out, or (b) when resistance is essentially infinite, in which case it never discharges and remains at dangerously high voltage for a very long time.
If mark value of capacitor is one microfarad and measured value by a DMM is .87 microfarad. Then capacitor is ok or not. Waiting for your kind reply...
Hello good evening, if I understood correctly if by putting the test points with the sound and it sounds it means that the coil is not good, and if it does not sound then the coil is still good, right?? 🤔
Hi... My capacitor does not show the ohms number on its sticker... but when I did test, as you showed, the multimeter quickly shows numbers and thereafter goes back to 1. I also would like to know, if it's damaged, whether that could have been cause for the magnetron to get damaged?
Do the other tests. If there is no continuity between the terminals & the body then it is ok i guess. And yes this can be the cause of magnetron to get damage.
How long does it take for microwave capacitor to get discharged. If I kept my microwave plug off for a month and open. Does it still have harmful level of current in it?
Not sure. Better use a plier with covered handles and touch both the connectors of the caps few times. That will surely discharge the caps if any charge left.
Hi thanks for the info. I've been searching for one piece of information prior to messing with the capacitor in my microwave. I realize you need to discharge the cap but I'm trying to understand if it's safe the check the cap with my digital multimeter while it's still in the microwave. I have the microwave unplugged but I want to be able to determine if the cap still has a charge and if so, what the charge is. I'd like to be able to test it with my multimeter prior to discharging the cap to see exactly how much charge it's holding. This is the one thing I can't determine after watching multiple videos and searching the internet. Thanks.
Check if capacitors have internal resistor (usually 10Mohm). If yes then you should leave microvawe unpluged for a while and capacitor should discharge itself via this internal resistor. After that it should be safe to test it. However have a look at this site - it provides more information regarding capacitor discharge and danger associated with it: www.repairfaq.org/sam/micfaq.htm#micsafdc
what if the resistance between the two terminals goes up for just a second or so then goes back to Ol, it does not stay at 10M ohms? I think it is bad correct? Continuity test was normal.
hay what happens if when you testing ohm reading goes beyon ohm it'ts rated for, let's say it's a 10 ohm, when you test goes up to 19ohm is it norma??? or not a good sign??
Hi , thanks for the video. I tested my diode using a 12 volt battery, it shows 8 V and in the other direction 7V . Is is also faulty ? Greeting from Hungary
Hi, is my Capacitor faulty if I can read Resistance (after discharge) only few seconds (values are jumbing from 400 then 200 then 900 and then it is showing infinity => 1. My capacitor is similar as yours -> capacitor has 1.05mF 2100v typ CH85 21105 with 10M ohm.
@@technoboy-allinOne that one on the multimeter, I can not get the values as you in your video from 3:05 to 3:30. In my case values on the multimeter jump very fast and in less then 1 second it is showing infinity 1
I check the impedance but multimeter is very slowly rising and it takes almost 3 minutes to rise 1 mohm, is it normal or is it faulty? (Cont. chk seems ok)
@@technoboy-allinOne thanks for your comment I did replaced the capacitor. However I also suspected my old multimeter and bought an new mm as well and, when I checked the old capacitor it proved to be ok! So one should make sure that the tester is reliable.Just wrote down for information.🙋♂️
@@johnmacedo4483 John, microwave capacitors have resistance and capacitance. Cheap multimeters are not reliable for this tests. his statement about not resistance between the capacitors connectors is wrong, but you need a good Fluke meter to read this resistance. It is about 0.8 to 1 ohm. This internal resistor is to discharge the capacitor when you turn off the oven. I have a Fluke 87 muiltimeter that reads this value but my automotive Fluke 375 does not. In is reliable to test microwave capacitor you need an expensive capacitor ESR tester. Igt will give you in one shot the reading of internal resistance and capacitance. Or like me, having a hand good capacitors and magnetrons at hand to test to the units.
Leak caps will show as short, terminal to the body. Caps test mode is not available in all multimeter except some costly ones. So these are the other ways
@@petermendonca807 You can not use a multimeter to test a microwave capacitors because they have resistance and capacitance. The only way to test this capacitors in a reliable manner is using good capacitor tester that are costly, with that I mean over $100.00.
Show a closeup of the multimeter so we can see where your setting is for continuity. I searched the setting on google and they say the OHM is the continuity setting.
It seems as though I do not have continuity between the terminals but in the second step I don't get a reading of having any Ohms(@3:23). Is this possible? And if so I guess my capacitor is bad? Thanks.
In the beginning of your video you should absolutely make sure that dealing with those high voltage capacitors can kill you. 2100V is no fun to be shocked with!!!
If the resistance is good then. If you have high end multimeter with capacitance tester then you can test the capacitance directly & also the resistance. This is the way to test with basic mutimeter. In most cases resistance also gets effected in bad caps. So you wouldnt get right value.
@@technoboy-allinOne when tested with capacity function don't show anything. We suppose that is because of the build in resistor that is blocking capacitor charging... Idk.. When plugged in with 2A safety the transformer start heating much and smoking after a while. And now idk what is bad... When testing transformer coils everything seams to be ok. Except heating coil shows 0.03 and then dropping to 0 omhs. In other people's cases it stayed at approx. 0.03
My capacitor is not in short. But I get only 1.238 megaohms. My capacitor has 10 megaohms in description. Probably, my fuse was damaged because of it. Could you assure of it ?
Yes its faulty. Thats the 10 megaohm resistance inside the capacitor. If its showing less then the actual value, that means its faulty. Replace it. And also check the diode. Better replace that too.
@@technoboy-allinOne Thank you. I made a simple test with diode. I used three piles and my multimeter. I put the piles in serie and put black wire in the negative polarity (pile) and red in diode (where I put a screw) and the other diode side I put in positive polarity of pile then I got half of electricity of piles (three) and nothing when I inverted the multimeter wires. I used dc voltage in multimeter.
Check the capacitor with your multimeter using the capacitance function if equipped. Since your meter maxes out at 2M you are out of luck. You'll need to borrow a higher ranged ohm meter. FYI, the 10M is referring to the built-in dump resistor in parallel with the capacitance. This dump resistor ensures no charge remains across the capacitor terminals after power is removed. I typically don't short out the terminals if I know the unit is healthy. I seldom receive a jolt from caps. These caps don't retain enough energy to harm humans. They will not electrocute humans!
Thanks for the "Heart". What's crazy is that I have absolutely no recollection making this comment and can't believe I came up with wordplay so clever.
Doesn't work: my capacitor (2kv) leaked blowing the fuse but this test at only 5 volts doesn't show any leakage. Your test shows a false good. Only a high voltage test CAN test a high voltage capacitor.
