leds -- How to hook up

What kind of LEDs are those?

What voltage to they require?

I see a + for the white wire and a - for the gray so I assume they work on DC.

Now, if you gave them too much voltage, its possible you have burned them out already.

"Cut 1 off", as in one indvidual light, or one strip of three?

The lights work in groups of three, on up to 12 Volts DC.

I think you might need to connect the grey and white at one end to each other to complete the circuit.

White goes to the + on your DC power supply. Grey goes to -.

Each of these three LED segments use 12 volts DC for power.  You MUST use the correct polarity, note the + and - on the strip.  It's really as simple as that.  If they didn't light on 12VDC from a wall-wart, you did something wrong with the wiring, or they've been damaged.

I also suggest you try lighting a single three-LED segment first and get your power right.

If you want to run them on AC, you'll want a diode to rectify the AC.

SUCCESS,

  with 1 LIGHT GROUP OF 4,

1) Leave 1 end unconnected

2) Make sure you have , the correct end, on wall warts, 

    this netgear, has a faint, grey seperation on 1 of the wires

  THe dang things will stay dimly lit approx 30 -45 seconds after disconnected

thanks

edit:  how many of these 20 will run on 1 wall wart -  wall wart says 12v ~ 1 A

Each three LED group takes 20ma, so you can run about 50 of the three-LED clusters on the 1A supply.