ErnieHorning Posted November 13, 2013 Share Posted November 13, 2013 Can I ask you to RE_READ Max's first post (post #3) and tell me again that we do NOT need triac's then ? We can use SCR's in our controllers and get the SAME results as TRIAC's ? PPPLLEEAASSEEEE !!! (Sarcasm intended) Actually, technically you could. It would require a full wave bridge before the SCR. You then would have rectified DC and then the SCR would operate with exactly the same end results. Many of the old multi-function strings used this method. It requires one extra part though. You could substitute two SCR’s for a TRIAC but then you would need to drive one of the gates with a negative voltage. Kind of complicates the circuit though when TRIAC’s are so cheap. You can substitute an SCR with a TRIAC since most TRIAC’s will accept both a positive or negative gate voltage. Link to comment Share on other sites More sharing options...
plasmadrive Posted November 13, 2013 Share Posted November 13, 2013 Actually, technically you could. It would require a full wave bridge before the SCR. You then would have rectified DC and then the SCR would operate with exactly the same end results. Many of the old multi-function strings used this method. It requires one extra part though. You could substitute two SCR’s for a TRIAC but then you would need to drive one of the gates with a negative voltage. Kind of complicates the circuit though when TRIAC’s are so cheap. You can substitute an SCR with a TRIAC since most TRIAC’s will accept both a positive or negative gate voltage.There are caveats to those statements, but for the most part, yes. However, if you were to use back to back (anti parallel) SCRs, you most likely would not have most the dimming or flickering issues with the LEDs compared to the triacs. This is because each SCR would have 1/2 a cycle to turn off and the capacitive nature of the twisted wire strings would not matter so much. Link to comment Share on other sites More sharing options...
Santas Helper Posted November 13, 2013 Share Posted November 13, 2013 1 Link to comment Share on other sites More sharing options...
plasmadrive Posted November 13, 2013 Share Posted November 13, 2013 LOL @ Santa's Helper.. Link to comment Share on other sites More sharing options...
ErnieHorning Posted November 13, 2013 Share Posted November 13, 2013 Careful... Link to comment Share on other sites More sharing options...
plasmadrive Posted November 13, 2013 Share Posted November 13, 2013 OMG!! LMAO Link to comment Share on other sites More sharing options...
Ken Benedict Posted November 13, 2013 Share Posted November 13, 2013 Max... RMS and IPP (like the way Sears use to advertise their guitar amplifiers, 250 watts IPP, (6 watts RMS)) or something like that.... That IPP is Instantaneous Peak Power that is usually achieved milliseconds before the amplifier loses it's Magic Smoke. It's quite misleading, but the sales people like it. Link to comment Share on other sites More sharing options...
plasmadrive Posted November 13, 2013 Share Posted November 13, 2013 LOL.. Link to comment Share on other sites More sharing options...
plasmadrive Posted November 13, 2013 Share Posted November 13, 2013 instantaneous puffing power? 1 Link to comment Share on other sites More sharing options...
Max-Paul Posted November 14, 2013 Share Posted November 14, 2013 Plasma, Where did you come up with the 1.57 X Avg.? I know of only two sets of numbers to use with RMS and peak. They are .707 and 1.414 So if you take 14mA X 1.414 you get 19.976mA. Really not familiar with your numbers, please enlighten me. Link to comment Share on other sites More sharing options...
a31ford Posted November 14, 2013 Author Share Posted November 14, 2013 .Guys... I wana thank ALL of you (yes, even Max.) I had a rough day at work, and to come home to all the banter (both pro and con) was worth the wait !!! ALL of you crack me up, but Plasma... IPP, a good one Greg Link to comment Share on other sites More sharing options...
Max-Paul Posted November 14, 2013 Share Posted November 14, 2013 I dont suppose any of you are familiar with the original plans to supply electricity to homes and businesses? Edison was going to at first supply D.C. power to homes and businesses. Didnt take them to long to realize IR drop would limit the transmission range from the power source. And the cables would have to be huge in diameter (aka gauge). So, They went with alternating current. The voltage can be stepped up or down and at a higher voltage the problem of IR drop is minimized. Smaller wire diameter can be used cause the current is low. But peak voltage does not do the same work as D.C. voltage. So RMS voltage is equal in working power as D.C. voltage. 1 Link to comment Share on other sites More sharing options...
Santas Helper Posted November 14, 2013 Share Posted November 14, 2013 uh hum...Plasma, Link to comment Share on other sites More sharing options...
Santas Helper Posted November 14, 2013 Share Posted November 14, 2013 I dont suppose any of you are familiar with the original plans to supply electricity to homes and businesses? Edison was going to at first supply D.C. power to homes and businesses. Didnt take them to long to realize IR drop would limit the transmission range from the power source. And the cables would have to be huge in diameter (aka gauge). So, They went with alternating current. The voltage can be stepped up or down and at a higher voltage the problem of IR drop is minimized. Smaller wire diameter can be used cause the current is low. But peak voltage does not do the same work as D.C. voltage. So RMS voltage is equal in working power as D.C. voltage. I'll be a deer eating popcorn. I did not know that.Seriously Max-Paul, that was good info.Thank you. Link to comment Share on other sites More sharing options...
plasmadrive Posted November 14, 2013 Share Posted November 14, 2013 Actually Max, I did know that. There was a thing on PBS about Westinghouse vs Edison. Big battle it was. Very interesting all that went on.. Link to comment Share on other sites More sharing options...
plasmadrive Posted November 14, 2013 Share Posted November 14, 2013 Plasma, Where did you come up with the 1.57 X Avg.? I know of only two sets of numbers to use with RMS and peak. They are .707 and 1.414 So if you take 14mA X 1.414 you get 19.976mA. Really not familiar with your numbers, please enlighten me.1/.637=1.5698... or 1.57. Link to comment Share on other sites More sharing options...
Max-Paul Posted November 15, 2013 Share Posted November 15, 2013 Still does not mean anything to me Plasma. Where did you get those numbers and what are they suppose to represent? Cause I know for a fact that they have nothing to do with the conversion to or from RMS and Peak? Link to comment Share on other sites More sharing options...
Max-Paul Posted November 15, 2013 Share Posted November 15, 2013 Oh BTW, I had a few minutes today to give this some thought. As you mentioned the voltage goes from a positive 110v to a negative 110v one one hot wire and mean time the other hot wire goes from a negative 110v to a positive 110v. So between the two hot leads you have 220v. But we are working with voltages that would be found in a home. And in a home you will also have a Neutral wire. This wire is a reference point, it does not swing from positive to negative, but the hot lead does. Thus, I will not step over to the dark side.... Link to comment Share on other sites More sharing options...
Santas Helper Posted November 15, 2013 Share Posted November 15, 2013 Link to comment Share on other sites More sharing options...
plasmadrive Posted November 15, 2013 Share Posted November 15, 2013 Still does not mean anything to me Plasma. Where did you get those numbers and what are they suppose to represent? Cause I know for a fact that they have nothing to do with the conversion to or from RMS and Peak?.637 x Vpk = avg value of the full wave pulsating unfiltered DC waveform. Remember, pulsating DC is measured in terms of Avg and not RMS. So you are correct about it not connecting to RMS. Much of the misconception you may be having Max might have to do with terminology. For example, you don't measure capacitance values in terms of nanometers.. you also don't measure pulsating DC in terms of RMS. Link to comment Share on other sites More sharing options...
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