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View Full Version : Power supply tester for RIPPLE testing


9912199
04-14-09, 02:10 PM
Most of power supply testers are testing for voltage level and presence only. This is a BIG mistake.

Power supply very rare have problems with voltage level because it uses feedback loop for regulation and this circuit almost never goes bad. This mean if bad capacitor causing low voltage feedback line will force primary stage of the power supply to provide more power su get desired voltage. The result is that end user with tester does not see this.

Biggest problem are high ESR capacitors. Now if we have power supply with bad capacitors these will almost always pass test with standard power supply testers.
Bad capacitors will not be able to filter if we apply load, this way we can see ripple, however, power supply testers provide load on 12V line only, even this one is not suficient enought.

So the questions is:

Did anybody make power supply tester that test for voltage, ripple level and provide load for each line? If so where to buy one?

hokiealumnus
04-14-09, 02:17 PM
You'd probably have to supply your own load and use an oscilloscope to see how clean the power is.

SuperMiguel
04-14-09, 02:36 PM
You'd probably have to supply your own load and use an oscilloscope to see how clean the power is.

agreen you can do it with the use of an oscilloscope

Oklahoma Wolf
04-14-09, 02:47 PM
Did anybody make power supply tester that test for voltage, ripple level and provide load for each line? If so where to buy one?

Can't be done for any reasonable cost a consumer would be willing to pay. The problem is, you need to get the supply being tested to over 80% of full power first. Then, you can measure the ripple and noise. It would cost hundreds if not thousands of dollars to come up with something like that.