Max-Paul Posted January 4, 2015 Share Posted January 4, 2015 No a GFI is not a magic bullet. A short between the hot lead and the neutral lead will not trip a GFI. Now if the short is between the hot lead and earth ground then a GFI will trip, but even so might still not be fast enough to protect the triac. There are many triacs out there that has had only one half of the circuit shorted. So damage can be as fast as 1/120 of a second. Link to comment Share on other sites More sharing options...
Ken Benedict Posted January 5, 2015 Share Posted January 5, 2015 Thanks wbaker4, I guess that's another can of worms.. i saw something about snubber on another thread. Keep in mind that there are TWO types of "snubbers"; the LOR kind (usually a 47K ohm resistor across the load) and the electrical/electronics industry standard to keep inductive spikes from damaging other components. These are referred to as RC or RCL type. The LOR snubbers are actually "ghost loads" or "dummy loads" that are used to drain the voltage down so that flicker-type lights or LED type lights work properly.If you don't want to build your own, you can use a C9 light or a night light or a Glade Scent device to accomplish the same thing.They're even sold commercially: http://www.bhphotovideo.com/c/product/748716-REG/American_DJ_LED_DUMMY_LED_Dummy.html If you don't have a dimming problem, then you don't need one. 2 Link to comment Share on other sites More sharing options...
plasmadrive Posted January 5, 2015 Share Posted January 5, 2015 I have been trying to get the Christmas light community to use standard terminology on this subject for the last 3 years without much success. Ken it 100% correct. A real "Snubber" related to triacs is circuit (usually an RC network) used to snub or dampen inductive spikes or kickback. The use of the term "Snubber" relating to the dummy load for resistively draining off the capacitive effects of an LED string is not a good use of standard terminology relating to triacs and their loads. Since most of us use LOR for non inductive loads like Christmas Lights, when you see the term "Snubber" in these threads you will most likely find the context dealing with LED strings that do not dim as desired. Rarely will you see it in the context relating to inductive kickback or spikes. 1 Link to comment Share on other sites More sharing options...
Max-Paul Posted January 5, 2015 Share Posted January 5, 2015 Plasma I agree with you and you know how I feel about this stuff that people are calling X Core where all of my life we called X conductors or X pins on plugs/sockets. Ok I agree snubbers are in the electroincs / electrical usage is usually a RC circuit. So what do you suggest then what we should call this resistive load put on an LED string to help with a smooth fade? Link to comment Share on other sites More sharing options...
wbaker4 Posted January 6, 2015 Share Posted January 6, 2015 "So what do you suggest then what we should call this resistive load put on an LED string to help with a smooth fade?" How about calling it the last resort? Link to comment Share on other sites More sharing options...
plasmadrive Posted January 6, 2015 Share Posted January 6, 2015 No a GFI is not a magic bullet. A short between the hot lead and the neutral lead will not trip a GFI. Now if the short is between the hot lead and earth ground then a GFI will trip, but even so might still not be fast enough to protect the triac. There are many triacs out there that has had only one half of the circuit shorted. So damage can be as fast as 1/120 of a second.I think you meant it won't trip as a ground fault (low current) but will trip as a breaker with high fault current... Yes ? In any case, you are so correct.. not even close to fast enough for protecting a solid state device. Plasma I agree with you and you know how I feel about this stuff that people are calling X Core where all of my life we called X conductors or X pins on plugs/sockets. Ok I agree snubbers are in the electroincs / electrical usage is usually a RC circuit. So what do you suggest then what we should call this resistive load put on an LED string to help with a smooth fade?We should call it what it is.. a dummy load. You could call it a "bleeder" but that would be another can of worms.. ha ha.. "So what do you suggest then what we should call this resistive load put on an LED string to help with a smooth fade?" How about calling it the last resort?LOL! Yep.. pretty much! Link to comment Share on other sites More sharing options...
Max-Paul Posted January 6, 2015 Share Posted January 6, 2015 I think you meant it won't trip as a ground fault (low current) but will trip as a breaker with high fault current... Yes ? NO! I think my statement is true as I stated it Plasma. In any case, you are so correct.. not even close to fast enough for protecting a solid state device. We should call it what it is.. a dummy load. You could call it a "bleeder" but that would be another can of worms.. ha ha.. LOL! Yep.. pretty much! Link to comment Share on other sites More sharing options...
plasmadrive Posted January 6, 2015 Share Posted January 6, 2015 Max, GFCI receptacles will in fact NOT trip a function of over current, but a GFCI breaker WILL trip as a function of over current. I know a lot of the old houses still have those panel mounted contraptions. I should have been more clear. Link to comment Share on other sites More sharing options...
wbaker4 Posted January 6, 2015 Share Posted January 6, 2015 (edited) Anyone seeing glitches on their lights may want to consider changing the 220 ohm resistor to 180 ohms (for 115v installations). It seems that 220 ohms may just be a bit outside the margin to supply adequate gate current in some instances. R = Vp / Itsm 115*1.41 / 1A = 162 ohms Itsm is from the spec sheet for the MOC3023. Perhaps LOR can add additional info? ---- I have not tried this yet, but will make the modification on one of my controllers soon. Edited January 6, 2015 by wbaker4 1 Link to comment Share on other sites More sharing options...
Orville Posted November 28, 2015 Share Posted November 28, 2015 "So what do you suggest then what we should call this resistive load put on an LED string to help with a smooth fade?" How about calling it the last resort?Perhaps a LORmabob? LOL With the definition being a 47K resistor, C7/C9 "incandescent" bulb, Glade Air Freshener or even a short strand {10-20} incandescent lights plugged into the end of an L.E.D. light strand for proper dimming and fading purposes for L.E.D. strands that flicker, flash or shimmer when faded or dimmed. You know kind of like a thingamabob or thingamajig. Link to comment Share on other sites More sharing options...
Gary N Posted November 29, 2015 Share Posted November 29, 2015 robongar There is a video on you tube that shows an idea of how to change a traic, it is under Lighting Up Paxton. I was just asking the same questions about traics the other day. I ordered some from the mouser link, shipping was about $5.50 to northern Wisconsin. Happy Holidays, Gary Link to comment Share on other sites More sharing options...
Orville Posted November 29, 2015 Share Posted November 29, 2015 Not sure if I ever brought this up before, but why aren't the Triacs "socketed"? It would be much quicker and easier to change one out if they were in a socket instead of soldered directly to the PCB. Is it because of cost or is there some other reason LOR has never used sockets for the Triacs? In essence, it would seem more prudent to use sockets as opposed to not. For one thing, since the Triacs are mounted to a heat sink via hardware, they couldn't just fall out or become dislodged by bumping the controller around. Plus if the end user bought a ready made unit in a box, they wouldn't need or require soldering skills to replace a failed Triac, just unscrew the Triac from the heat sink, pull out of socket and put in the new one, reattach with hardware and you're done. So just curious if LOR had or has ever thought about using sockets instead of direct soldering Triacs and if they did, why was the reason for not using a socket? 1 Link to comment Share on other sites More sharing options...
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