Berko/Eckon Four Aspect Signal Wiring Up DC Controlled Layouts

The rotary switch is a very popular choice for track sections and also cab control due to the multiple contact and position options. These are sold in singles & multi-packs, supplied with & without the knob that goes over the long spindle. They come available in many different pole & way options, the one we’ll be using is a three-pole four-way rotary switch. A typical example of a rotary switch can be seen opposite right.

Rotary switches have the poles in the center are labelled A upwards depending on the switch variant. The one in the diagram is a three-pole & thus the three poles are labeled A, B & C. In the diagram opposite right are shown as the three orange circles labelled A, B & C. The switch ‘Throws’ are called ‘ways’ and the ones shown in the diagram opposite as yellow circles, & has 12 ways.  The way terminals are always divided by the poles. So for example (depending on how many poles & ways the switch has), pole A is connected to way 1 – pole B to way 4 – pole C to way 7 etc, when we twist the switch pole A goes to 2 and pole B to 5 and so on.

In the wiring diagram opposite of a Four aspect, colour light signal shows how the four aspect signal is wired up to a three-pole four-way rotary switch. The power supply is via 12v DC from a stand-alone 12v transformer such as those sold by Gaugemaster, or via the 12v uncontrolled outlet on your controller.

The red wire marked + Pos (Positive) & the black wire marked – Neg (Negative) are connected to the 12v DC power supply & feed both the signal & switch. The red wire marked + Pos goes to one of the centre tags/Poles marked A in the centre of the switch. As shown in the diagram.

The black wire – Neg (The common return) goes to the common return wires on the signal. On Berko/Eckon signals, the common return wires are usually coloured white & have a resistor pre-fitted (or supplied with resistors for fitting by the modeller). Resistors typically should be of a value of around 1K for the signals. In the diagram opposite, can be seen two – Negative wires coming from the signal. The black wire on the right-hand side of the signal is the common return from the red, green & lower yellow LED’s on the signal & has a resistor fitted. The second black wire which is on the left of the signal, is the common return from the upper yellow LED on the signal. This again has a resistor fitted as well. both resistors should be of the same value i.e: 1K.  

The wire from the red LED (The red line from the signal to the switch in the diagram) goes to the way tag marked as number 1. The lower yellow LED (The yellow line from the signal to the switch in the diagram) goes to the way tag marked number 2. The green LED (The green line from the signal to the switch in the diagram) goes to the way tag marked number 3. And finally, the upper yellow LED (The orange line from the signal to the switch in the diagram) goes to the way tag marked number 4.

The upper yellow LED (aspect) should only illuminate when the lower yellow LED (aspect) is lit. This is done via a diode which is used to provide a feed path from the 2nd yellow LED (aspect) switch position to the lower yellow LED (aspect) feed. This allows both yellow LED aspects to remain lit when the switch is set to the 2nd yellow LED (aspect) position.  

So by turning the knob on the rotary switch cycles through turning on & off the LED’s (aspects) of the signal as needed. Of course, the signal can be automated, either by using the likes Heathcoat Electronics signal controllers or building your own signalling circuits. Further details of the signal control units can be found on Heathcoat Electronics websites.

Happy modelling