2 traffic lights become one project help required...
2 traffic lights become one project help required...
(OP)
Hi all,
I have two systems that each have their own traffic lights (red/Green lights). However, using two traffic lights is not OK and therefore need to combine the outputs from each system into a a controller of some kind that provides an output to a single traffic light.
Requirement:
Only once both systems give a green status/output may the traffic light turn green, all other times the traffic light is to remain RED.
i.e.
i)
SYSTEM 1 GREEN
SYSTEM 2 RED
TRAFFIC LIGHT - RED
ii)
SYSTEM 1 RED
SYSTEM 2 RED
TRAFFIC LIGHT - RED
iii)
SYSTEM 1 RED
SYSTEM 2 GREEN
TRAFFIC LIGHT - RED
iv)
SYSTEM 1 GREEN
SYSTEM 2 GREEN
TRAFFIC LIGHT - GREEN
INPUT and OUTPUT information:
Signal from system 1:
3 wires (red light, green light & common)
12V DC (flashing)
Signal from system 2:
3 wires (red light, green light & common)
110V AC (Solid)
Output to the traffic light:
3 wires (red light, green light & common)
110 AC (Solid)
Anyone that can help and provide a diagram/description of how this can be achieved it would be much appreciated!
Thanks,
A mechanical engineer that has no electrical knowledge whatsoever!
I have two systems that each have their own traffic lights (red/Green lights). However, using two traffic lights is not OK and therefore need to combine the outputs from each system into a a controller of some kind that provides an output to a single traffic light.
Requirement:
Only once both systems give a green status/output may the traffic light turn green, all other times the traffic light is to remain RED.
i.e.
i)
SYSTEM 1 GREEN
SYSTEM 2 RED
TRAFFIC LIGHT - RED
ii)
SYSTEM 1 RED
SYSTEM 2 RED
TRAFFIC LIGHT - RED
iii)
SYSTEM 1 RED
SYSTEM 2 GREEN
TRAFFIC LIGHT - RED
iv)
SYSTEM 1 GREEN
SYSTEM 2 GREEN
TRAFFIC LIGHT - GREEN
INPUT and OUTPUT information:
Signal from system 1:
3 wires (red light, green light & common)
12V DC (flashing)
Signal from system 2:
3 wires (red light, green light & common)
110V AC (Solid)
Output to the traffic light:
3 wires (red light, green light & common)
110 AC (Solid)
Anyone that can help and provide a diagram/description of how this can be achieved it would be much appreciated!
Thanks,
A mechanical engineer that has no electrical knowledge whatsoever!





RE: 2 traffic lights become one project help required...
You also may have to deal with the flashing aspect of the green that flashes - or maybe not depending on the equipment.
Usually traffic signal lights are controlled by heavily certified electronics that have specific inputs and outputs.
Are you just winging it?
Keith Cress
kcress - http://www.flaminsystems.com
RE: 2 traffic lights become one project help required...
Dan - Owner

http://www.Hi-TecDesigns.com
RE: 2 traffic lights become one project help required...
Its a little bit of winging but the systems we are using a for simple control systems - nothing regulated per se.
Know any students that would want to put something together for us then MacGyver?
RE: 2 traffic lights become one project help required...
TTFN
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RE: 2 traffic lights become one project help required...
Take it to the local university or tech school... students get "real world" experience they can put on their resume, you get a solution for dirt cheap. Everybody wins, and I wish more companies offered such experience to upcoming grads...
Dan - Owner

http://www.Hi-TecDesigns.com
RE: 2 traffic lights become one project help required...
RE: 2 traffic lights become one project help required...
If you could reuse the System 1 status lights, and could accept the flashing, then the solution might be very simple: use a 120Vac relay controlled by System 2 Red to redirect System 1 outputs to the Red light.
In other words, System 2's Red signal would force System 1 to flash its red bulb (no matter what).
One relay, maybe a diode or two.
A complete solution would perhaps include consideration of failure modes. It depends on the safety im
RE: 2 traffic lights become one project help required...
(Unintentional post break, but a bit funny given the topic of the sentence.)
RE: 2 traffic lights become one project help required...
When a controller goes to green status, the amber and red are off. So when a signal goes to green, amber and red will be off until the other controller is green.
Usually not acceptable in the real world.
With no information regarding the controllers, an attempt at solution is almost futile.
A complete solution will probably require a PLC. A simpler, easier solution may be to just use a PLC and lose the existing controllers.
Sure sounds like class work when you don't want to tell us the application.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: 2 traffic lights become one project help required...
Sometimes called 'tower lights', almost (but not quite) as confusing a name as 'traffic signals'. Used in factories to indicate go/nogo status of a machine. Perhaps his boss wants him to combine the status of two machines.
RE: 2 traffic lights become one project help required...
RE: 2 traffic lights become one project help required...
RE: 2 traffic lights become one project help required...