Model Railway Forum

forgive the stupid question folks but which side is the negative on this GM controller?

The minus signs are negatives.

Those with a solid line and a dotted line change depending on whether you select forward reverse.

Those with a wiggly line are AC.

Can only just see the picture. The output to the track ( 0-12V D.C. ) does not really matter. If the wires are the other way round then the train just goes the other way. The track power is overload protected so it is not an issue if you get it wrong for the track power outputs.
A 16 or 18 Volt AC output does not have a + or - as it is an AC current which fluctuates back and fore. This AC current is ideal for powering point solenoids (E.g. Peco). Remember though that the AC output does not have overload protection so doubly check the wiring for accessories.
I believe you also have a seperate 12V DC which is designed for powering lights, turntables etc. (I believe Tortoise pointmotors work from a DC current so this extra supply (If it is what I think) would be ideal. This extra output should be marked + and - (And I believe it is). This output will not have an overload cut out to it (Assume it does not just incase) and will be a fixed 12 volt (Or 14 volt if labelled as 14). It is a fixed output meaning that it stays at the voltage shown, which is different from the track outputs which are variable by nature in order to vary the speed of the locos being controlled.
I hope this explains things a little.
The only thing to find out in regards to the controller is if it is suitable for common return wiring methods or not. I believe Gaugemaster controllers are but make sure just incase. That way you can either take advantage of the common return wiring method to save wire or you can double up the wiring and wire the traditional way. Some modellers I have seen on youtube confuse the issue by referring to cab control as common return which it is not. Cab control can be wired as common return but it can also be wired without using the common return wiring method. It all sounds complicated but it is actually simple once one has learned the principles behind it (Which is relatively easy. Is more about it being explained in a way one can understand then it being complicated).

MG. you need to click on pictures to increase size.

Thanks. I didn't think of that. I was trying to enlarge the picture as it stood which ad the effect of losing its clarity.

As Rog says the —/... indicates DC but the polarity will be changeable from the knobs/switches on the controller face, hence you connect it by trial and error to suit convention. I.e. right rail is positive in the direction of loco travel - generally on track direction of travel is right to left to accord with a train entering a station from that direction. Note not all 1:1 UK stations abide by this rule.
The Aux is + & - as indicated. The wavy line indicates AC.

Many thanks folks I am just a bit rusty on the wiring configuration attached is a photo of the common wire connection using a vortrax 4 way controller and GM'S



Please excuse the photos absolutely terrible, will have to get better ones if anyone can even make out the wiring just let me know what you think,and yes I agree once I have the wiring done it is simple its just the relearning curve i'm on

The photo is good. I didn't think of clicking on it.

Hi
I don't quite understand what the terminal block connectors are for in the wires from the controllers?

Basically, simple common return just needs the wiring to use totally separate supplies for every feed connecting to the common return wire. i.e. each item MUST be fed for a totally separate transformer or from a dual wound transformers secondary winding. Sharing of a transformers output is not permissible where Common Return is to be used.
This very simple drawing shows the very basic idea using four controllers and feeding four tracks with one return wire.

Hi Brian

Many thanks for the Drawing. The reason you see the blocks are the connections from the transformers really only has room for one set of wires. So I just used choc blocks because 2 wires fitted better into them