Which power supply seems more appropriate?

[Wade Lippman]

My wife has several LED "trees" on the deck. One of them stopped working. The power supply tests dead, and the tree lights up on 3 batteries; so I presume the power supply is the issue.

https://www.tractorsupply.com/tsc/pr...hted-2228880ec

It is 4.5vdc, 0.8a.
I throw all my power supplies for defunct products in a bin, as you never know when you will need one. Well, today might actually be the first time it paid off!

I have one that is 5vdc, 2a. and one that is 4.5vdc, 250ma. Any guesses as to which might be more appropriate?

Oddly, though one claims to 8 times the wattage of the other, they are both the same size and weight.

[Paul F Franklin]

The 4.5v unit is underated current-wise compared to the original supply; but I'd probably try it first since the trees may draw less current than the original supply was rated for. Worst case it won't work or will overheat. If that one doesn't work, then try the 5v. Very unlikely the extra voltage will hurt anything. If you have a way to measure DC current, measure the draw of the trees using the battery as the power source. If it's over 250 ma, then skip trying the 4.5v unit.

[Rod Sheridan]

Use the 5 volt supply.......Merry Christmas, regards, Rod.

[Jim Koepke]

Oddly, though one claims to 8 times the wattage of the other, they are both the same size and weight.

Weight and size doesn't have much to do with the output of DC power supplies.

They may have the same transformer with different wattage components.

It may be coincidental.

jtk

[Wade Lippman]

Just to make it more fun, the one marked 4.5V measures 9v, and the one marked 5v measures 5.1v.

I think that pretty much decides it for the 5v.

[Myk Rian]

It will read 9v because there is no load on it.

[Wade Lippman]

It will read 9v because there is no load on it.

That's what I thought, but then why those the 5v read 5.1v instead of 10v?

[Wade Lippman]

It has been running with the 5v power source for 2 hours now. It is noticeably brighter than the one next to it, so I guess I should expect it to burn out eventually?