I am assuming you are referring to changing polarity on the frog ? A change over switch like built into some solenoids or slow action motors like Tortoise or even a microswitch that works in conjunction with the tiebar. For DCC, there are auto frog changers - an example https://www.gaugemasterretail.com/gaugemaster-bpdcc80-dcc-autofrog.html It all depends on how the turnout/point is operated.
Hi Ron Minimum is a single pole double throw (SPDT). Or you could use a micro-switch in contact with the tie bar, when you move the point tie bar from normal to closed it will trigger the micro switch. Three connections on the SPDT or microswitch - Common, Normally Open (NO) & Narmally Closed (NC) Connect the common to the point V With the point in the Normal position. The normally closed is connected to the track that blade is touching. The normally open connection is connected to the other rail. Paul
Another option is a SPDT slider where you also mechanically operate the point by attaching a wire, e.g. Mercontrol wire into a hole drilled into the slider switch toggle. For a 3 way point you need two seperate switches. Jim
Still confused on the actual wiring of the switch. I wired the frog to the centre connector then + to one side and - to the other but it only worked in one direction??
Have you checked with a multimeter, depending on the point manufacturer and the condition of the contacts between the blades and the stock rails this sort of problem can arise with a loco stalling on the blades. Jim
Which is which on the switch? I wired the middle to the frog and + & - each side but that doesn't work??
Hi Ron Hopefully this will explain it The switch will have 3 contacts, an SPDT will have the common in the center, with a multimeter check the resitance or continuity between the center pin and each outer connection The one with 0 resistance is the normall closed connection. The other high resistance or no continuity connection is the Normally open connection Moving the switch to the other position will now have the Normally closed connection open, and the normally open connection closed. From the above diagram, the common is connected to the Point V The normally closed connection is connected to the rail that the point blade is touching, and the normally open is connected to the other rail. The same applies to the slide switch Jim mentioned You will need to check which is the common, it may be the middle pin or one of the two outer pins - use a multimeter or continuity checker. If you drill a hole in the black plastic knob you can thread a wire to the point tiebar and use that to mechanically operate the blade while the switch changes polarity of the V. Limit switches again are similar However the slide switch is probably the easier solution. Paul
A little late, but I use a micro switch under the layout, or in fact on top of the baseboard... Cheers, Gary.
Me too in places, particularly in accessible non-scenic areas where the point is simply operated manually and the end of the micro-switch arm can be placed directly against the tie as in your images. Jim