Right power supply for 5050 led strip

I have 5050 led strip 60 led/m, and I have a power supply I want to use to power it on Now I got some specs online (not sure if right ones?) for 5050 which say:

150 LED Count: 36W


Now, say I want to have a strip of 50 leds. Does it mean they will draw 12W? My power supply says PSA15W-120. Does it mean 15 watts at 120V?

• How do I know that this power supply will not burn the leds?
• Why don't I need a limiting resistor here?

Some other specs for this strip will talk about current consumption, but not sure how to go about it in calculation.

Now if my power supply is 12V and leds draw 12W, will the current be 1A? Now I have to say that ofcourse I did connect the strip to the supply and it works, but how do I know that neither is get damaged over time?

I know there are a few questions here, but for a seasoned electonicist probably are no-brainer. I appreciate any help or reference to a relevant article.

• You might find this answer answers most of your questions. – Transistor Aug 26 '16 at 8:09