Clay disc capacitor-how to accurately test it - hardware

The last condition I mentioned about electrolytic capacitor breakdown when under load. In this condition I will talk about the high voltage resin encrusted ironstone china disc capacitor. In cpu monitor, it is hang around used in the barrier voltage (G2) line at the crt board. When it fails, it can cause inconsistent or from time to time raster brilliant and dim and at times no display.

Adjusting the flyback transformer broadcast be in charge of will not solve this problem. You can cut off the catch as whether if it cause by a defective fly back or G2 line at crt board. Confiscate the G2 wire from tour and amount the broadcast voltage with a digital multimeter- it ought to have a continual voltage (will not vary). If the voltage is not committed be wary of the fly back. If it ok then trace the barrier voltage circuit. As a rule this route consist of only resistors and capacitors. At times a defective crt socket might cause this type of catch also!

Many times a tech can't solve this intermittent or no demonstrate conundrum is as their digital capacitance and ohmmeter calculated ok on the capacitors. The capacitors in the barrier voltage line are as a rule rated of 102,103, and 472 1kv to 2kv. A 'missed' in glance this capacitors will caused the technician can't solve the problem, if he address exchange the capacitor. An intermittent capacitor can pull down the barrier voltage causing the demonstrate problem.

As mentioned earlier, an ohmmeter with 12v amount produced and a digital capacitance with 3v harvest are powerless to accurately check the capacitor that have the rating of 1-2 kilovolt!

If you have the analog filling tester or meter, the panel will show a short path when a selection of voltage are pump in to check the high voltage capacitor. The voltages that you can cliquey is depends on the brand or model you buy. Some have the range of 50v to 1000v and some have the range from 100v to 500v. It is elective whether you must have one. If you have one then it would be an added gain for you. The other alternative that you have is to aim interchange the supposed capacitor. In my country, you can get a new one in less than US150. 00 or you may bid a used unit from eBay.

As for me, inspection the small blue resin covered pottery disc capacitor that have the capacitor code of 104 50v, also using digital capacitance meter to check for the value, i also use an analog meter set to times 10Kohm that have the harvest of 12v to check this type of capacitor. Many times it will naked the bad intermittent capacitor. You will be shocked to see the capacitance meter checkered ok but show a shorted conception when check with analog multimeter.

In the marketplace there is a number of brand of analog multimeter that have the range of 100kohm. If you open up the cover, you can't see the 9v sequence in it, what you see only the 2 pieces of 1. 5v battery. This type of meter can't accurately become aware of the short in the capacitor for the reason that the amount produced voltage is only 3volt!

For those of you who complicated in repairing monitor, you will agree with me that examination the flyback domestic capacitance- quite often you get the right value 2. 7nf with digital capacitance meter but when you alter on the monitor, you will hear a 'tick-tick' sound from the flyback. This is since the capacitor is infringement down when under load. If you did not do everything with the flyback, in stages the domestic capacitance will befall shorted and you will need to fix up the flyback.

Jestine Yong is a electronic repairer and a writer. For more electronic get working again in a row delight visit his website at http://www. noahtec. com/electronic-repair-articles. htm