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S10xGN

RETIRED!
Joined
May 26, 2001
Messages
2,563
Hi All,

I've built a landscape lighting system using a Malibu 200W transformer and twenty 1-watt LED lamps. I really want to use a photocell trigger, but I've gone through 3 Malibu photocells and have got less than a month out of each of them. I'd like to build one that will last.

These transformers puts out 12V A/C. The LEDs run great on A/C and supposedly last twice as long. I'm thinking of using a TRIAC to switch the A/C and a phototransistor (or photoresistor, but NOT cdS) to sense the light, but have no clue how to combine them into a circuit. Will the phototransistor need to be rectified? Do solid state components work the same with A/C? Anybody want to sketch this up for me?
 
I'm no electronic guru but it sounds like the 'turn it on' part takes quite a bit of current like a electric motor on start up. Is there a way to put a relay in there to put the current through so it doesn't burn out the photo cell? I'm guessing that is what a TRIAC is but don't really know.
 
That's pretty much what the TRIAC is, an A/C relay with a trigger. But I'm not sure if the trigger will work with A/C, or how to incorporate the photo device into the TRIAC...
 
Being in the electrical field for 18 years and licensed, maybe I can help you out.:biggrin:

Install the PC on the 120v side of the transformer. What type of PC are you using?

Here the wiring if you have a PC with white, black and red wires.
-Neutrals (whites): 120v white/neutral input, Transformer and PC all get
spliced together
-Line (black): black 120v line input splice with black of the PC
-Load (red): red of the PC splice with the black of transformer

If have any other questions, just ask. Please post a pic of your installation.

Hope this helps

Billy T.
gnxtc2@aol.com
 
I agree switch the 120V primary side of the transformer with the photocell circuit say from outdoor lighting products and switches from Homey Depot.

Gotta be easier than designing and then trying to waterproof a secondary circuit off the 12V side.

Outdoor photocell circuit waterproof is what you need.

Where is everything going to be located such as wiring and transformer and such and what type and location of primary power?

Designing stuff takes planning and ALL the details have to be known to make the best decision on what to use and where to locate it.
 
The pi$$er is, this is a factory photocell, the 3rd one that "doesn't" work (If you try the link, there's a place to get the PDF file for this piece). I have no idea what's killing them, but they initially work for a few weeks before dying. When they "die" they pass only 1.9V instead of 12V. I think I'd prefer to stay on the low voltage side, thanks, unless you can recommend an engineered full-packaged setup.
 
The pi$$er is, this is a factory photocell, the 3rd one that "doesn't" work (If you try the link, there's a place to get the PDF file for this piece). I have no idea what's killing them, but they initially work for a few weeks before dying. When they "die" they pass only 1.9V instead of 12V. I think I'd prefer to stay on the low voltage side, thanks, unless you can recommend an engineered full-packaged setup.

Ditch that factory set up. Malibu Lighting is junk (no offense). Just install the PC on the 120v side. Go to an electrical supply house and get a genuine PC. If you send me a pic of your install, I could recommend what you have to do to correct your problem. That link of that PC looks like water is able to get inside the PC and kill it. Water meaning moisture also.

If you want real landscape lighting, look into Hadco and Kichler.

Billy T.
gnxtc2@aol.com
 
Ditch that factory set up. Malibu Lighting is junk (no offense). Just install the PC on the 120v side. Go to an electrical supply house and get a genuine PC. If you send me a pic of your install, I could recommend what you have to do to correct your problem. That link of that PC looks like water is able to get inside the PC and kill it. Water meaning moisture also.

If you want real landscape lighting, look into Hadco and Kichler.

Billy T.
gnxtc2@aol.com

Billy,

The Malibu transformers work great, it's just that d@mned photocell. Your suggestion of the Hadco is what I'm looking at now, I'd never heard of them before (thanks!). You're saying I need to cut the 120V plug off the transformer and wire the photocell in?
 
Billy,

The Malibu transformers work great, it's just that d@mned photocell. Your suggestion of the Hadco is what I'm looking at now, I'd never heard of them before (thanks!). You're saying I need to cut the 120V plug off the transformer and wire the photocell in?

What is the rating of the photocell? Is the PC rated for incandescent/inductive loads? What are the specs on the photocell?

Do not cut the plug off the transformer.
 
What is the rating of the photocell? Is the PC rated for incandescent/inductive loads? What are the specs on the photocell?

Do not cut the plug off the transformer.

The Malibu cells have no ratings of any kind. Hadco sells several types including 12V and 120V, rated for either type of load. I'm waiting on them to advise which would suit my application the best. Thanks again for your link to Hadco.
 
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