It's correct, but do not forget to place a fuse. If something goes wrong, it will avoid future headache, fire... Marcelo Y. Darren wrote: >Could I eliminate the Vcc Circuitry? That would make it much simplier for >learning and just use some batteries or another wall wart. How would that >effect the circuit in regards to zero crossing? > >How can the TRIAC work if I hook the load up between Hot IN and Hot OUT? >I've read everything and I'm just having trouble understanding why there are >3 wires at JP2. One of them has to be duplicate so to speak. If the >connection was made between Hot in and Hot Out. > >So Therefore. White is as we know White. Hot In is I guess Black... >The circuit goes Hot Out is where the load is connected between the triac >and then back to Hot In. Wow is this schematic bad. The Jumper will have >to have 2 wires connected to pin 3 and 1 on JP2. Thats what confused me so >much. Here is what I think the schematic should look like. > >In otherwords the Load or the light bulb is connected directly to mains, but >because of this stupid jumper its all very confusing. Is this correct >people? I made a diagram and its quick and ugly but it does show the >important Mains connections. > >Darren King > >----- Original Message ----- >From: Mark Willis >To: >Sent: Thursday, December 09, 1999 2:24 AM >Subject: Re: Microchip Appnote Dimmer Problem. > > >> Ummm... Fun one >> >> Fansler, David wrote: >> > >> > Darren - I do not pretend to be an expert - but here is what I see. >> > 1. The schematic does not totally match the article >> > 2. The load would go between Hot Out and Hot In. >> >> I don't like the "hot out" term at all; Originally I was misled, here - >> I'd expect the load to go between Hot Out and Return, given that >> terminology! Hot In is power from the power grid, and, Hot Out is >> pulled towards Neutral/Return from Hot In by that Triac, to light the >> bulb - so I'd have called that Lamp Return instead, or something like >> that. So yep, David's right, and this is just plain murky terminology >> Not an electrician, I guess? >> >> > 3. You would supply a Neutral (white wire) to Return. >> > 4. You would supply Hot (balck wirefrom power company) to Hot In >> > 5. Ground (green) is a good idea. It can be tied to Neutral (which >is >> > done in US breaker boxes). >> >> Definitely a good life-saving idea. >> >> > 6. Vcc is generated by the circuit above the PIC (RV1, R1,2, C1-3, >> > D1-3) >> > 7. I would take JP1 to be an external input to allow control of the >> > circuit by an outside source (another PIC, automation system, etc.) >> >> For safety, I'll add this: If you're going to use JP1, please DO verify >> that "Neutral" isn't hot with respect to the Ground line, before or >> during installation; If it is and you connect a switch pair to J1, >> touch a lead on that & grab something that's grounded, and you can be >> killed. So - please be a little careful there! >> >> Probably a good idea to verify that anyways, I've seen a few mis-wired >> houses. (Some with 3-prong outlets throughout the house, none having >> ground wires attached, almost bought that place... Would've run ground >> wires soon!) >> >> > 8. While simple, a fair warning is given in the article that this >> > circuit has no isolation from the AC main and therefore can bite you! >> > 9. If used for lighting purposes, this circuit will produce >filament >> > hum at low light levels (larger filaments hum more) A large choke in >line >> > with the load will kill the hum. >> >> Have it hum "Singing in the rain" for us Seattle area webbed-footed >> folks? >> >> > David >> >> I'll add another finnick: I just plain *detest*, dimmers that come on >> "Full Bright" when the light's "off". BAD idea; I lose my night vision >> so as I later walk down the hall, I step on the cat & get bit & >> scratched, trip on the cat scratching post, step on the sharp metal >> piece the cat knocked off the shelf and bleed on the carpet, and by then >> I'm getting "displeased"... With Full On, I get far more light than I >> want or need, it wastes energy (as I dim the light way down & leave it >> on all night, instead of turning the light OFF, due to the huge >> annoyance of losing night vision) - and it's really hard on the bulb! >> >> I'd have the bulb come on at 10% or so, and ramp up fast if the user >> holds down "Brighter", but not full on to start with; Ick. I've heard >> the excuse, "But - full on, instantly, will scare a burglar worse"; I >> seriously doubt it, a sane burglar is going to be FAR more concerned >> about an occupant turning the light on to 20% - so they still have night >> vision, and can still see to chase the burglar, or to get into position >> inside the place to hold them for police, far easier than with the >> lights coming on full brightness - so the occupant's Blinded completely, >> I'd think. >> >> If you blow a bulb up, that might spook the burglar more; Why use a >> dimmer circuit to blow bulbs up, though? Use it to extend bulbs' life, >> instead! >> >> Mark >> >> > -----Original Message----- >> > From: Darren King [mailto:darren.king@SYMPATICO.CA] >> > Sent: Wednesday, December 08, 1999 2:44 PM >> > To: PICLIST@MITVMA.MIT.EDU >> > Subject: Microchip Appnote Dimmer Problem. >> > >> > http://www.microchip.com/Download/Appnote/Category/rDesigns/40171a.pdf >> > >> > >> > I have looked at the above 100 times and I'm still confused. I don't >really >> > want to build this circuit without understanding it. I really hope >somebody >> > could help with this one. I'm not familar with the Hot in - Hot >Out -Return >> > (White). When I see White I know what that means. So which of the hot >in >> > and hot out is supposed to be the black? Is the green wire used? Does >the >> > load hook up between the Hot Out and the Return? What is Vcc supposed >to >> > be? Is this where I hook up the load? What is RV1? As you can seem >I'm >> > not an electronics wiz, but understanding this would help out greatly. >As >> > you can read, I'm really lost. >> > >> > Darren King >> >> -- >> I re-ship for small US & overseas businesses, world-wide. >> (For private individuals at cost; ask.) >> >