Replacing switch with a timer

Replacing a light switch with a timer witch that controls the outside roof soffit lighting. I removed the switch. It is a single pole. However the wires are 3 blacks and one open copper. I figure the copper exposed is the ground since it going to the green screw. There is two blacks going to one screw plate and then 1 black going to the other end screw plate. How do I kno which is the hot. Load. (Is there a neutral wire too)? The two.blacks going into one area confuses me

These switcher timer lights have 4 colors wires. Red/black/green/blue vs my 3 blacks and ground

Existing:
Leviton Decora 15 Amp Single Pole AC Quiet Switch, White (10-Pack)-M32-05601-2WM - The Home Depot

Timer:
http://pdf.lowes.com/operatingguides...04750_oper.pdf

this one switch controls 8 lights.

 

Welcome to the forums! We can't see inside the box, but there should be a bundle of white wires with a b cap on them. Those are your neutrals. You do not switch neutrals, only hots. You would test the wires using an analog volt meter probing the black wire to ground. Most likely the two wires will be "hot", since it appears to be a feed through to another switch. The PDF you provided doesn't show multiple colored wires, only black white and green/bare. Clarify that for us, or show us a picture of the actual back of the switch/timer

 

As Larry said, the looped hot wire is your source. Connect that to line.
Snip the loop, straighten and strip the 2 wires and connect both wires with a wire nut to your timer's line in.
The other single black wire is your load to the lights.
You should have no problem finding a bundle of white neutrals to tie into.

You should test with a meter to confirm.

 

Ah okay, so the two black should be the HOT line. if i use the volt detector it should display 120 on each of those then?

the single black is the load

the neutral - if i look in the back of the box and see it connected to another neutral line, is it okay to detach and leave the other neutral detached or it has ot be hooked up to something?

I will get a picture up once I am back at the home. Thanks for the input so far! its fun!

 

If you mean a multimeter, yes. All neutrals must be connected together.

 

Thanks guys!

Dug deeper into the box and found the two white neutral wires. Use the multimeter and discovered the single black wires was the hot ,and the other two black lines was the load. Was able to attach all 4 areas into the designated slots on the switch and got the timer to work. The meter tool is such a great tool!

 

Good job. Thanks for letting us know.