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Power supply output voltage fault

Posted by: Aubreyhu on Fri, 09/03/2021

Hello, all
I bought a LED driver:
input: AC100-240V
Output: DC30-57v / 600mA (constant)

I connected it to a led strip, they flashed several times then switched off (i suspect they died, so i check the LED Driver Failure Analysis and Maintenance to detect), then took the multimeter and measured the Output voltage, and it was around 74V, but failed.

I suspect this is what killed the leds.
My question is: am I missing something ? This power supply is supposed to output max 57V. Why does it show 74?
Is the power supply faulty? Or did I measure it wrong?


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LED driver test 62.05 KB


Submitted by PI-Zek on Tue, 09/07/2021

I just need some details in order to help you:

1. What are the specifications of the LED strip that you used? The fault may be due to overloading.

2. What is the model number of the power supply? It is possible that 74V is the no-load output voltage of the unit. We can check in the datasheet of the power supply.

To check if the power supply is working well, the power supply should deliver 600mA to your load (you can use your multimeter to measure the current) if you use an LED load/strip with a total voltage in between (30V to 57V). The LED should be able to handle more than 600mA current.