Ubiquiti US-16-150W Dead After Power Outage

In this video, we attempt a repair of a Ubiquiti US-16-150W switch which was taken from a customer's site.
Forgot to mention in the video - after repair, the power output of the Switch Mode Power Supply board (model number:G0398-15011480A V0.7) was a stable 53.5V DC

[@geoffedwards189]

Well done. Thanks for your clear explanations.

[@amanbin]

Great video and explanation

[@PowerSupplies]

Give Avanti Power Repairs a call on repairing the power supply

[@NickMitchell-kj8ci]

Thanks for the video and explanation of the board and how it works. Where did you get the replacement components?

[@therepairshare673]

Hi Nick, I took one from a spare board I had here, but I would usually order from either Farnell or Radionics here in Ireland. It's a standard 450V 150uF capacitor, but you just need to be careful with the height - if the replacement is too tall then you wont get the switch case back on!

[@BH_ROHIT]

thanks for good explanation video.i got same model switch , it gives 53.1v at point your supply was giving 40v., only fans working, in start for few days lan lights blinking but now no light atall just working fan. if you able to suggest what can be checked.

[@therepairshare673]

Hi there, if you are measuring a stable 53.1V coming out of the DC power supply, then it is most likely that your switch power supply is fine. I would guess that your problem is with the other board.

[@einfelder8262]

Can you let us know what the output voltage was after the repair, please. Also, if you know what the rated amps of the power supply is. Thanks.

[@therepairshare673]

Hi, I measured it now and the output of the power supply board is a very stable DC voltage of 53.4V. I don't know what current it is rated for. I found it difficult to find out anything about the power supply board (model number:G0398-15011480A V0.7) when troubleshooting. Are you seeing the same issue?

[@einfelder8262]

@@therepairshare673 Thanks, I believe the unit is rated at 2.9A. Mine just died, will be removing it later today to see whether it's just the big cap or more. I will probably just replace it with a Meanwell LRS-150-48. You can max the volts on that to near 54V but the switch is happy with 48V as long as you don't have too many high draw POE devices on it.

[@therepairshare673]

​@@einfelder8262 I would be concerned that if the Ubiquiti main board did not see the exact 53.5V voltage, then it might not work. I think I would be looking for reassurance that it would definitely work with 48V before purchasing the Meanwell. If I were in your position, I think I would focus on seeing if your fault is the same as mine, and if so, work on getting the cap replaced. I cut through the heatsink to get access to the cap from above. You only need a soldering iron to remove the filter cap, just remember to discharge the cap before removing in case there is any voltage sitting on it.

[@einfelder8262]

@@therepairshare673 The unit is now working just fine on the Meanwell. You can turn it up to max ~52.7. The board only wants 48V, the 6V headroom is for powering up POe devices that have a large startup drain. There are none on this system. To get the right size cap delivered to me is ~$30 and 3 weeks. Not an option.

[@therepairshare673]

@@einfelder8262 Great. Glad you got it sorted.

[@NicolaFavazza]

In mine the integrated U1 exploded, do you know what it's called?

[@therepairshare673]

Below are the numbers that I see on U1 TEA 1755T NXP SK51.108 rXD16351 Send an email to therepairshare at gmail.com and I will send you a pic of the chip.

[@NicolaFavazza]

@@therepairshare673 Thanks! Do you think that beyond this IC one has burned something else?

[@therepairshare673]

@@NicolaFavazza Hi Nicola, it's very difficult for me to say without seeing the board or testing. I think the best you can do is test for other shorts and look around the board for other failed components, and if everything else looks okay, take a chance on replacing just that chip.

[@NicolaFavazza]

@@therepairshare673 I try to change it..I'll let you know ) Thanks