Troubleshooting bathroom LED light fixture

Thread Starter

getterdun

Joined Jul 28, 2019
3
First time user trying to determine how to test the ENP021C0700SED1 circuit board on an Eaglerise light fixture.

The problem is that the lights on the fixture (three lights with multiple leds each) does not work. Referring to the attached photos, I've tested by connecting 120v AC to the black and white input wires, and determining that there is no output voltage across the red and black wires.

That's as far as my knowledge goes; but, I'd like to figure out what the problem is and fix it just for my personal satisfaction. Over the years I've been stumped by other similar electronic problems with appliances and cars, and I'd like to learn more about electronic circuit troubleshooting.

What would you do next to test this board?

Thank you.
 

Attachments

Hymie

Joined Mar 30, 2018
1,284
Fault finding a switch mode power supply such as this requires the minimum of a scope and an understanding of the principles of switch mode power supply operation.

I would recommend you investigate replacing the unit with one having the same output voltage and power rating.
 

Thread Starter

getterdun

Joined Jul 28, 2019
3
Fault finding a switch mode power supply such as this requires the minimum of a scope and an understanding of the principles of switch mode power supply operation.

I would recommend you investigate replacing the unit with one having the same output voltage and power rating.
Thank you for taking your time to help me on this. I had not heard of "switch mode power supply"; so, last night I watched some Youtube videos about them, which were very interesting.

I had already searched for this specific unit (ENP021C0700SED1), found it on Alibaba, and sent an inquiry re buying one. However, I've not heard back from them. Since you said I should investigate replacing it with one having the same output voltage and power rating (thanks for the suggestion), I'm now looking for one. In that regard, I'm downloading a picture of the case cover in the hope that you can easily tell me a suitable substitute. Please don't bother though if this is any trouble for you: I don't mean to be asking you to do work I should do -- just thought you may easily know this, and I've already spent an hour looking without success.
 

Attachments

panic mode

Joined Oct 10, 2011
2,736
actually that would not be a direct drop-in replacement since it has extra feature - dimming which needs 0-10V input. not sure how it would operate if dimming input would be left open. if shorted, voltage is zero so light would be off.

non-dimmable product with matching specs would be GSC25B-700 from MEANWELL which is also about half the price.
 

Thread Starter

getterdun

Joined Jul 28, 2019
3
Well, after reviewing the GSC25B-700, I agree with you that it ought to work. It just will not have the dimming function, which is not being used anyway.

I did discover that there is a fuse (or thermistor or ?) at in input power lines, and it did not have continuity. I then removed the fuse, and soldered in a wire where the fuse was. I thought this was going to fix the thing, but alas, no joy.

Anyway, before ordering this, I tested the LED lights themselves and got inexplicable results. I cut the red and black wires at the board, stripped off the cover at the ends, and connected first a 9v, then a 27v battery (3 nine volts in series) to them. This had no effect on any of the three LEDs, even when reversing the battery leads. Then, I cut two wires leading to just one LED light for testing. Again, no effect. I expected some effect for both of these tests, but got none. So, I'm stumped.

Hopefully you can tell from the above whether the LED light itself is bad before I order the replacement SMPS.

Thanks again for all of your help.
 
Top