Electrical question

Here's one available on Amazon:
Time delay relay. $13.99

It can be set to run without a trigger signal.

From the manual:
P6: Relay will turn ON for time OP after power on without
getting a trigger signal and then relay will turn OFF for
time CL and then loops the above action. The number
of cycles (LOP) can be set.

One lamp would connect to the NC side of the relay and the other to the NO side. You would also need a source of DC power.

Wow-- great suggestions and quick ! Thanks---- I'll do a little more digging and get something working

Biastable 555 circuit through an optocoupler and SCR's

It looks like this would work fine.

Connect power to the A1/A2 terminals, the hot to pin 15 and each of the lights to pins 16 & 18. The 'on' time will be for one output and the 'off' time for the other. Both times are independently programmable from 0.1s to 100days. Less than $30.

I use several of these at work. A couple of them have been in use for a few years, and no failures yet. Use a couple cheap relays, one NO and one NC to achieve what you are trying to do.

Or make it easier and just use a cheap PLC. :)

agesilaus wrote:
Maybe this if the description was written in plain english.

Pretty cool.

This may do what you want:

Programmable Traffic Light Controller


It's got many modes of operation (including red-green flashing, which should work for your application) with programmable flash times up to 2 minutes. The outputs are rated up to 240VAC and 640W (probably @ 240V, so around 2.5A per contact, you might want to add output relays).

Theses two items should accomplish what you are trying to do.

https://tinyurl.com/1etvb485

https://tinyurl.com/fv9qpoxf

Here is a loop timer on ebay. Then you just need a relay so when the timer has one on it will turn the other off.

OK ebay links don't always work. Search this: Timer Switch Outlet Nearpow Multifunctional Infinite Loop Programmable

Probably more than one way to do this.

Maybe this if the description was written in plain english.