Basic electronics 101

[steveparrott]

Quick point of correction: low voltage lighting transformers are stepping down from 120V AC to 12-22V AC. They don't convert to DC. (Although I've heard that LED's generally run off DC.)

If you want to check your work on voltage/amperage calculations go to the CAST Lighting calculator at http://www.cast-lighting.com/volt-calc.html .

[Frog Lights, LLC]

LED's are 12 volt ac and use very little current and last for 11 years. LED lights are the wave of the future and that is why Frog Lights, LLC is the leader

[greywynd]

Originally Posted by Frog Lights, LLC

LED's are 12 volt ac and use very little current and last for 11 years. LED lights are the wave of the future and that is why Frog Lights, LLC is the leader

Well, unless something's changed, LED's are light emitting diode's which only allow current to flow in one direction. However, if you put them in an AC circuit, they will allow one half of the current to pass. If you were to use an oscilloscope to watch the current flow in this circuit, only one half of the sine wave would be there, the other half would be 'chopped' off.

[Frog Lights, LLC]

Yes , that is correct. Actually the chip is 3.6 volts d.c. but in low voltage lighting it is associated with a circuit to allow it to be used along with the other lights at 12 volt a.c.
Of course LEDs , with associated circuits, are used in many applications now including car and truck lights at 12-24 volts d.c. , traffic lights, and numerous other installations using high voltage a.c.

[fixer67]

LED driver basics. I have LEDs running off 110 and 220 at my house. See picture below for tech.

[greywynd]

Originally Posted by Frog Lights, LLC

Yes , that is correct. Actually the chip is 3.6 volts d.c. but in low voltage lighting it is associated with a circuit to allow it to be used along with the other lights at 12 volt a.c.
Of course LEDs , with associated circuits, are used in many applications now including car and truck lights at 12-24 volts d.c. , traffic lights, and numerous other installations using high voltage a.c.

Ahhh, I see, the basic LED is still the same, there's just the appropriate circuit in each light to supply the LED with what it requires, using 12V a.c. as the source (the lighting controller.) It's been a few years since my electronics courses, I didn't think the LED's would have changed.

[kevinsky]

Originally Posted by arosewag

I try to run 1 'main' line to a spot that is approximately equal distance from each of the lights that will be on the zone, then run a secondary line to each fixture. Easy to troubleshoot if ever a problem, and keeps voltages similar.

I call that the Hub method. Are all those secondary wires the same length even if one fixture is further from the hub than another?

[arosewag]

You could use the same length for the secondary runs, but I don't.

[arosewag]

Can anyone explain why an x-10 switch for incandescent lighting will not work with other types of lighting or appliances?

[fixer67]

Originally Posted by arosewag

Can anyone explain why an x-10 switch for incandescent lighting will not work with other types of lighting or appliances?

I take it you are taking about the X-10 remote switch system like the ones you can buy at RadioShack
TWO reasons. Reason #1 ,Some X-10 switch system do not turn off all the power but let just a little bit though so they have power to run. Reason #2, X-10 switches use a SCR switching circuit meaning the out put is really a pulsed DC output and not AC. Incandescent lights will run of just about any type of signal. Fluorescent lights and AC only motors will not, infact if you try to run Fluorescent lights and AC only motors off of a pulsed DC all you will do is fry it. If you can find a X-10 switch that has a TRIAC output which is two SCRs in reverse parallel that will give a an AC put out then maybe you can run your Fluorescent lights. NOTE= The X-10 wall outlets are either TRIAC output or relay output