Actual Size Traffic Light Controller WITH SWITCHPACK - Electronic Circuits Projects Diagrams Free

mrdexterous · 9th June 2003, 02:43 AM

Hello Again, I have a switchpack for an actual traffic light. The switchpack consists of 3 triacs, 3 sample LEDs and so on. There are 3 leads coming from the negative side of each of the test LEDS and one main lead coming from the postive side of all the LEDS (there is a trace connecting them). When you apply +12V DC to the postive side then touch any of the 3 remaining leads to ground (-12V) The same LED will turn on. This simulates that the Triac is working and will turn on and allow 120V AC to flow through it turning on a Bulb.
My problem is, my timing circuits are all backwards. For example my led is connected to ground and awaits a positive pulse to turn it on whenever the counter cycles to it. However the switchpack is always connected to +12V DC awaiting a negative pulse to turn it on. Can anyone offer me advice on how I can build a different circuit so I can implement my switchpack?? Many thanks to all who take the time to read this post.

**kinjalgp** · 9th June 2003, 05:48 AM

Triac is a good solid state solution but if you are not able to get it work, try using relays.

**kinjalgp** · 10th June 2003, 06:29 AM

Try this circuit:
Use astable multivibrator of 1 second. Using it you will get Green Time = 4 Second, Yellow = 2 Second, Red = 4 Second. Diodes used are 1N4007.
I have not shown Triac connections of other two transistor. They are same as the first one.

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9th June 2003, 02:43 AM	#1
mrdexterous	Actual Size Traffic Light Controller WITH SWITCHPACK Hello Again, I have a switchpack for an actual traffic light. The switchpack consists of 3 triacs, 3 sample LEDs and so on. There are 3 leads coming from the negative side of each of the test LEDS and one main lead coming from the postive side of all the LEDS (there is a trace connecting them). When you apply +12V DC to the postive side then touch any of the 3 remaining leads to ground (-12V) The same LED will turn on. This simulates that the Triac is working and will turn on and allow 120V AC to flow through it turning on a Bulb. My problem is, my timing circuits are all backwards. For example my led is connected to ground and awaits a positive pulse to turn it on whenever the counter cycles to it. However the switchpack is always connected to +12V DC awaiting a negative pulse to turn it on. Can anyone offer me advice on how I can build a different circuit so I can implement my switchpack?? Many thanks to all who take the time to read this post.

9th June 2003, 05:48 AM	#2
kinjalgp	Triac is a good solid state solution but if you are not able to get it work, try using relays. __________________ "There is no way to peace, peace is the way!"

10th June 2003, 06:29 AM	#3
kinjalgp	Try this circuit: Use astable multivibrator of 1 second. Using it you will get Green Time = 4 Second, Yellow = 2 Second, Red = 4 Second. Diodes used are 1N4007. I have not shown Triac connections of other two transistor. They are same as the first one. Attached Thumbnails __________________ "There is no way to peace, peace is the way!"