For typical LED or microbulbs, #22 should be adequate. If your signals are working semaphores, the motors might require heavier wire.
I route them to homemade terminal blocks (#6 machine screws through plywood. One nut holds the screw to the plywood, another holds as many wires as necessary to one terminal. Make them with as many terminals as you think you might need.) Then they are connected to a master lighting panel with banks of cheap slide switches. My lights run off a variety of low voltage transformers, all plugged into a single 120 volt multisocket surge protector bar with an on-off switch.
Depends on whether you want your railroad and traffic signals to operate. A full description of an operating Automatic Block Signal system, or the intricacies of an interlocking plant, are a bit beyond what I can try to put into a post. There have been numerous multi-chapter articles written on the subject.
[quote]
I have a few traffic lights or track signals that have the 3 or 4 position switches. It
seems that you need to cut and reattach the connecting wires if you want to mount the
If you are going to run a single LED that draws 20mA (0.02A) then you could drop all the way to 32 gauge if need be (dependant on Voltage on the wire and the length of wire). Using the suggestion for 22 ga shows that a 22 ga wire can handle 920mA (0.92A) or, in theory, 46 20mA LEDs.
#2: Answered with a question: Are the signals equipped with Bulbs or LEDs?
#3: This depends on your desired control scheme. Using the following picture:
3.A: If you want all the lights to be controlled simultaneously, aka all ON or all OFF, then a simple SPST toggle/pushbutton wired in series between the ‘battery’ (aka universal DC power source symbol) and point A. This will allow you to run only two wires (red & Black) from the switch/pushbutton at the controlpanel to your load(s). In the case of the picture, the loads are the 3 14V bulbs.
3.B: If you want to control the lights individually, then there are several options available. I will detail the simplest: Referring back to the given picture above, you would have to install SPST toggles/pushbuttons between Point A and Bulb A, Point B and Bulb B, Point C and Bulb C. This is 3x the number of toggles/pushbuttons than 3.A and depending on the scale at which you are planning your signal control, this could be a significant cost increase! Additionally, since the toggles/pushbuttons will be housed in a control panel, this means that instead of the 2 wires that ran from the control panel to the load in 3.A, now we have a minimum of 4 (3 from the switches to the loads and 1 common return).