I am trying to make a traffic light controller with just using 3/4 control relays that have NC and NO contacts. The first pushbutton makes the sequence go from Red to Red and Yellow and then to Green.
The second pushbutton makes traffic light go from Green to yellow to Red.

 

I think you might need timers as well as relays.

 

Hi Brigen,
Welcome to AAC.
Is this a homework assignment.?
E

 

I think you might need timers as well as relays.

I’m trying to do it without any timers.

 

I’m trying to do it without any timers.

How are you going to achieve the 3 seconds on amber between green and red without a timer?

 

Hi Brigen,
Welcome to AAC.
Is this a homework assignment.?
E

Yes it is. I’m a bit stuck on how the control

How are you going to achieve the 3 seconds on amber between green and red without a timer?

it doesn’t have to be 3 seconds, it can just be instantaneous

 

Yes it is. I’m a bit stuck on how the control

it doesn’t have to be 3 seconds, it can just be instantaneous

K-Map , logic gates, combinational logic. You will also need to throw in a few passives in there to make it work.

 

K-Map , logic gates, combinational logic. You will also need to throw in a few passives in there to make it work.

Wouldn’t I be able to use 3 control relays for all 4 of the different output states?

 

The first pushbutton makes the sequence go from Red to Red and Yellow and then to Green.

Hi B,
The operate time of a relay is in the order of 20mSec, there would be no other delay between R > R&Y > G for one button push.
E

 

Yeah I do understand that. The delay isn’t important. I just need the sequence to be followed