3010D power supply short - Page 1
Forum section: electronics / beginners

author: Jane
author_rank: Frequent Contributor
timestamp: July 22, 2022, 08:25:00 pm
content: I measured voltage with this 3010D power supply but accidentallyvery high voltagehappend to be on a measuring point. As a result, plus input of that power supply is shorted to ground.Is there a schematic available ? Or anyone already solved a such problem in the past?Thank you for help

author: Jane
author_rank: Frequent Contributor
timestamp: July 23, 2022, 08:15:13 pm
content: That power supply is made under different brands e.g. YIHUA PS-3010D.None knows about a schematic or how to repair it?

author: BrokenYugo
author_rank: Super Contributor
timestamp: July 23, 2022, 08:41:08 pm
content: Don't use a bench power supply to measure things, DMMs are cheap. How high voltage are we talking about? What sort of equipment was this?Open it up and look at the power electronics (bigger parts) near the output for signs of damage, check diodes and transistors with a DMM. Pics of both sides of the boards help others follow along.This is a very international forum, it is not uncommon for a thread to not really take off for a day or two, it takes that long just for everyone to have a chance to read it.

author: Gyro
author_rank: Super Contributor
timestamp: July 23, 2022, 08:54:31 pm
content: Looking at the web, the 3010D (30V 10A) is clearly an smps type. There are many potential hazards for an inexperienced person, including primary reservoir capacitors charged to mains peak voltage and the high likelyhood that the damage will be on the primary (non mains isolated) side. As this is the Beginners section, I must advise extreme caution.I am also confused about the details of what you actually did. What is "very high voltage" in this context? Detail may be important for diagnosis.

author: janoc
author_rank: Super Contributor
timestamp: July 23, 2022, 10:30:13 pm
content: Quote from: Gyro on July 23, 2022, 08:54:31 pmAlso, there are multiple types of "3010D" supply:https://www.amazon.com/3010D-III-Adjustable-Regulated-4-Digits-Alligator/dp/B09VL7ZZJPOr this:https://electrobes.com/product/yihua-3010d-30v-10a-direct-current-regulated-laboratory-power-supply/The "content" is unlikely to be the same.It being Yihua, it means that every corner possible has been cut. I am not sure I would even want to touch something like that.These supplies sell for about $50, I would just bin it. Probably the safest (and most economical) option available.

author: MrAl
author_rank: Super Contributor
timestamp: July 23, 2022, 10:41:26 pm
content: Quote from: Jane on July 22, 2022, 08:25:00 pmHello there Jane,It is probably a simple problem but the solution probably cant be found on the schematic anyway because they probably dont show the component you need to replace. It's a simple diode like the 1N5400 series.What they do is connect that diode directly in reverse parallel to the output terminals of the power supply so that if another power supply tries to power the unit in reverse the diode will conduct and sink the current and probably blow out in the shorted condition.It could also blow with a higher voltage input than the diode is rated for. Again the diode would blow out in the shorted condition so it has to be replaced.To replace it you have to remove the internal circuit board, then you can find it. It is mounted fairly close to the output terminals so look there. It is not easy to find without removing the board though you may not even be able to see it without taking out the board.Once you spot it, it will probably be cracked which means it burnt and became a short.It's a simple way to help protect the power supply from blowing out completely if something that provides power to the input gets accidentally connected to it. The same will happen if you connect a large 12v lead acid battery in reverse to the input terminal polarities.I hate to say it, but there could be other things wrong too if the diode didnt catch the fault in time, but the diode is the starting point. You can test it to see if it is shorted then replace it and hope for the best.I have a schematic for a similar power supply the HY3010E if that can help i can try to find it. It does not show the protection diode either but the connection is very simple as explained above.Good luck with it Jane, and i hope you can report back here on your progress with this power supply.

author: Jane
author_rank: Frequent Contributor
timestamp: July 25, 2022, 07:52:36 pm
content: Thank you for your replies particularly MrAl