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Forum Index : Electronics : light chaser
| Author | Message | ||||
| irishron40 Senior Member  Joined: 22/09/2014 Location: IrelandPosts: 251 |
 Hi trying to solve problem. I used all 1 watt resistors instead of just the one.( is this a problem ) I was measuring 28 volts at pin 16 of the cd4017 even though I fitted a zener diode with a 8.2 voltage drop ( what could have caused this problem )as the max voltage for a cd4017 is 15 volts if im not mistaken thx ron |
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phil99 Guru  Joined: 11/02/2018 Location: AustraliaPosts: 2135 |
The problem is the bridge rectifier, it prevents the common negative of the logic circuit being tied to the common T1 rail for all the triacs. If the ICs got 28V they may both be dead. Replace the bridge with the supply circuit in @oh3gdo's circuit in your decade counter thread. It connects the common negative to the T1 terminal of the triac. @oh3gdo's triac circuit You may need to increase the size of C1 as that circuit delivers less current than a bridge. R2 (100 ohm) is very important as it limits the capacitor in-rush current to a safe value. Once again be careful, live circuits are potentially lethal. An isolated supply for the logic and opto-isolators for the triac gates would be safer. Edited 2023-11-05 13:56 by phil99 |
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| irishron40 Senior Member Joined: 22/09/2014 Location: IrelandPosts: 251 |
thx phil , but now im totaly confused could you draw lines on my picture please? |
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| irishron40 Senior Member Joined: 22/09/2014 Location: IrelandPosts: 251 |
I made small error and now measure just over 4vdc only one light comes on but like you said the ne555 could be cooked. i have plenty of the 4017 , so hope i have an other 555 to check system great to have patients , im just a beginner , but enjoying it. want these lights for my trailer where I perfom music in ron |
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