Very basic questions about using DCC.
- Thread starter Sarah Winfield
- Start date
No, I'm still around. I needed to sort out some of my own problems.
Today I have been running a locomotive round my outer track. I still have the loops to sort out.
I must decide whether tis best to spend money on clamps as rail joiners seem to be my biggest headache or to spend that money on reverse loop modules?
Sarah Winfield
Today I have been running a locomotive round my outer track. I still have the loops to sort out.
I must decide whether tis best to spend money on clamps as rail joiners seem to be my biggest headache or to spend that money on reverse loop modules?
Sarah Winfield
Good to read you Sarah. Suggest Clamps will get you running quicker if that is what you really want, the reverce loops surely can wait? Plus reverce loop midules will immediately be a bit of a complication to you and wiring them will be easier if you have clamps cos you can use the screws for the wires!
So
Clamps Oh and before you ask Massoth Clamps they are easier to fit than other types that need Alun Keys
Reverce Modules
Yep, clamps and the DPDT switch for your reversing loop to start... the track is the foundation, if you have poor continuity, and then add the autoreverser, you will be beside yourself.
Greg
Greg
"you will be beside yourself" I've frequently thought there are two of me fighting one another for my attention.
So can I install as an interim measure DPDT switches the same as if I were DC, please?
Thanks,
SW
So can I install as an interim measure DPDT switches the same as if I were DC, please?
Thanks,
SW
It would be interested to know where the DCC controller is located and where the DPDT switch needs to be mounted to provide optimum operational involvement when say you want to change a train from going round the main loop in a clockwise direction to an anti-clockwise direction.
This might help make your decision.
This might help make your decision.
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I feel that the concept of a DPDT Switch for reverce loops needs to be thought about most carefully.
Yes it can be done and yes it will work. But it needs to be understood completely what you are doing. My thoughts having replied on this earlier would be to try to make the location as foolproof as possible. After all there may be visitors and things need to work for them as well.
So a switch mounted on a plate screwed to a rail as close to one of the points as possible. Switch Lever towards the Rail that the point is diverging from will mean track to that Polarity (I use Polarity as I cannot think of a better word). Lever the other way means Polarity that way. So long as the switch is changed while the train is in the Section all will be well.
But for peace of mind I would suggest a DPDT Centre Off Switch and the Train be stopped whilst changing.
This would most certainly be a cheeper option for Sarah but at least 3 Switches that will need to be by the Points and Track that they refer to for sensible use.
Yes it can be done and yes it will work. But it needs to be understood completely what you are doing. My thoughts having replied on this earlier would be to try to make the location as foolproof as possible. After all there may be visitors and things need to work for them as well.
So a switch mounted on a plate screwed to a rail as close to one of the points as possible. Switch Lever towards the Rail that the point is diverging from will mean track to that Polarity (I use Polarity as I cannot think of a better word). Lever the other way means Polarity that way. So long as the switch is changed while the train is in the Section all will be well.
But for peace of mind I would suggest a DPDT Centre Off Switch and the Train be stopped whilst changing.
This would most certainly be a cheeper option for Sarah but at least 3 Switches that will need to be by the Points and Track that they refer to for sensible use.
It would be worth spending a few bob on doing this scheme, even if it is only temporary, so that you can get a handle on the principles of return loop wiring and operation.
I take Dunnys suggestion as being a yes from him.
I take Dunnys suggestion as being a yes from him.
I have some centre off DPDT switches, small enough to be screwed to fit between the sleepers. One of these I modified yesterday by soldering a piece of wire diagonally across the end 4 terminals leaving the centre terminal un-soldered.
I think I have to wire this switch to each rail each side of the isolating joiners. The controller is them connected to the centre terminals, I think? Have I got that right please?
Sarah Winfield
I think I have to wire this switch to each rail each side of the isolating joiners. The controller is them connected to the centre terminals, I think? Have I got that right please?
Sarah Winfield
Not quite..
You wire the 'crossed' outer terminals to the 'mainline', and the centre terminals to the isolated loop-section.
You are only needing to reverse (the polarity) of this section.
So just to clarify, from the 2 centre connections on my DPDT switch I run wires to each rail in my dead section one each side?
The 2 sets of outer connections I run to the rail on each power side of my loop?
I know it sounds obvious to anyone else but to me I simply have to confirm what I understand is in fact what people are telling me.
There is an adage to understanding but for the life of me I can't remember it.
Hopefully if you agree to my interpretation of what you have said I can get on and finish wiring my switch.
Thanks.
Sarah Winfield.
The 2 sets of outer connections I run to the rail on each power side of my loop?
I know it sounds obvious to anyone else but to me I simply have to confirm what I understand is in fact what people are telling me.
There is an adage to understanding but for the life of me I can't remember it.
Hopefully if you agree to my interpretation of what you have said I can get on and finish wiring my switch.
Thanks.
Sarah Winfield.
Sarah, on an other thread there is a really good drawing of the DPDT switch
https://www.gscalecentral.net/attachments/sarah-switch-loop-png.238267/
https://www.gscalecentral.net/attachments/sarah-switch-loop-png.238267/
That'll work provided you add wires across the outer switch connections.
This diagram may also help, one pair of wires, A or B, it doesn't matter, go to the isolated section and the other pair to the "main line".
It helps to connect the middle terminals (pair B) first. The crossed wires sometimes get in their way when connecting these.
Yeah, and for DCC it's even easier than operating it with DC, since you will use the LEDs as in that thread where it was already explained... when the train is about to cross in/out of the "reversing section" just make sure you have a green light, if not flip the switch... completely no brainer..
Greg
Greg
Sorry there is still some confusion in my mind.
Looking at the drawing, where do the RHS (small circles) go to please?
SW
There are 6 circles, that match the 6 connections on a DPDT (double pole double throw) switch:
This picture also has the crossing wires that create the reverse connections:
This picture also has the crossing wires that create the reverse connections:
Thank you, that is exactly what I have done to one of my DPDT's.
Now I need to establish is exactly where all 4 corner contacts are connected to?
If you can help please?
SW
Now I need to establish is exactly where all 4 corner contacts are connected to?
If you can help please?
SW
You only need 4 wires (not 6) and don't have to connect to all 4 corners. look at Greg's picture of a cross-wired DPDT - there are only 4 terminals on this one which has been pre-built with cross wiring. So there are 2 connections at one end and 2 in the middle. Typically the centre pair go to the isolated piece of track and the other pair are connected to the main track power. (Actually for this use it doesn't really matter which pair go where, but I'm used to using DPDT switches for changing between two different DC controllers and the centre terminals always go to the track in that scenario).
The important thing is to make sure the polarity is correct according to which way the switch is pointing, ie. which "end" of the switched section you are going to drive into.
The important thing is to make sure the polarity is correct according to which way the switch is pointing, ie. which "end" of the switched section you are going to drive into.
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