Rotary switches - simple question!

[Grimberian]

Hi All,

I am getting to the point now where all my track is bought and laid(albeit temporarily, have not pinned / glued it yet, I want to make sure I am happy with the layout), and I need to think about wiring.

After discussion with Chimer and a few others on my layout thread, I have decided 5 sections and 3 controllers with cab control will suit my needs - straight in at the deep end.

 

I have read a couple of threads and think I have worked out that I will need 1 rotary switch for each section of my track, each rotary switch provides power to that section only, and each controller is wired to each rotary switch.

 

So, if that's correct, the question is, where can I get rotary switches that are 2 pole and 4 positions (3 controllers, one off)?  Maplin's seem to do only 6 positions, and a lot of other websites seem to do a lot more poles, which I don't think I need - or maybe I do and have got that bit wrong!

 

I have the wiring diagram in my head at the minute, I will post it later as this is the first time in ages I have had to do anything like this!

 

Thanks for all the help,

 

Paul.

 

[66C]

Hi Paul

 

Have a look at this page from Maplin:

 

http://www.maplin.co.uk/c/components/switches#Category:Rotary%20Switches&sort=&page=1&productsPerPage=12

 

You could use a 4 pole 3-way switch but this would not have an "off" position - so you may be better to use a 3 pole 4-way switch so that each section may be off if required.

 

Rotary switches of this type generally have a movable stop position so that the ways you do not need are blocked when the switch is rotated.  If you can get them it is better to use "break before make" types as otherwise the track would be connected to two controllers at once for a very short time when the switch is operated.

 

Other suppliers are likely to be cheaper than Maplin - have a look at Rapid Electronics:

 

http://www.rapidonline.com

 

And also CPC (part of Farnell) at:

 

http://cpc.farnell.com

 

Regards.

[APOLLO]

 I have decided 5 sections and 3 controllers with cab control will suit my needs

 

 

Each section (of track) will need its own rotary switch - so 5 needed

 

3 controllers so 2 pole (minimum) 3 way switches required. 3 way is the important bit here, more poles is ok, they are not used.

 

So 4 pole 3 way rotary switches will be fine.

 

Maplin do this for £2.29  http://www.maplin.co.uk/p/4-pole-3-way-rotary-switch-ff76h

 

Think of it this way

 

 

In from controller 1 pos,

                                                                      

In from controller 2 pos,              Out Section positive  (to track)

                                                                       

In from controller 3 pos,

 

 

In from controller 1 neg,

                                                                      

In from controller 2 neg,              Out Section negative (to track)

                                                                       

In from controller 3 neg,

 

I've used several rotary switches this way.

 

Edited to add, as 66C writes above, you (may) need an off position, either use a separate on / off switch on the section feed AFTER the rotary switch or use a 3 pole 4 way switch, the fourth "way" being unwired therefore off (no feed to section)

 

Brit15

[Suzie]

The switches have an adjustable stop, so you can use the 6-way ones which will give you future proofing against buying more controllers (unused positions will just be extra 'off's in the meantime if you don't move the stop).

 

When using rotary switches with more than two ways and centre off you can have the issue when selecting a controller that the switch has to pass through the position of a controller that is controlling another section where a train is running and you will get a momentary surge of power, so think about using a separate toggle switch for 'off' and just using the rotary switch to select the controller.

 

If you have common return wiring (with suitable controllers) you only need single pole switches and can reduce the wiring somewhat which in your case will probably be quite a lot of wiring to save.

[Grimberian]

I am using a Hornby HM2000 controller which provides 2 of the controls, and another of the simple controllers that comes with the starter sets.

 

I think I need to go and do a bit more research into how to wire these things up, unless someone can provide a simplified wiring diagram for me?

 

Thanks for all your help so far, saved me going out and buying random stuff that probably wont work!

 

Paul

[Suzie]

Paul

 

Those controllers will be fine for common return wiring.

 

 

[RAF96]

I use qty 3 off config 2 x 6 rotary switches in series with a pair of push button switches and a CDU to fire my 18 points.

 

As stated by others the rotary switches have adjustable stops so you can have any 2 inputs (in my case straight and turn commands from the CDU and PBs) and as many outputs (in my case 18 solenoid points motors (3 switches x 6 selections)) as you like up to the switch limit or,...

 

... the other way around as many controller inputs as the switch allows (upto 6) and pos/neg outputs to your section. 

[DCB]

I have 3 pole 4 way rotary selector switches for 4 controllers and the lack of an "Off" position is a nuisance

The 3rd pole was to be for indicator lights to show which controller was selected.

 

My switches are arranged so Normal is straight up, Controller Inner Main = A pointer straight up.   Outer Main, B Controller, Loco Depot C Controller, Fiddle Yard D.

 

The switches are open frame but have been working for 25 plus years with no failures or issues

 

I also wired points with a Rotary and push button but to select any one of six in my case roads through a Capacitor and diode matrix using the type of switches |Mapiln sell, again they have worked for 20 years,

 

Knobs are a problem, the shafts need shortening on most switches but I mount my open frame ones on the back of the 2X1 baseboard frame and have the shafts running through the wood.  Some Fiat Heater knobs are very good for Rotary switches, 

 

Wiring is simple as long as you establish which outer ring tags connect to which inner ring tags, you need a meter with enclosed switches but you can see with the open frame ones.  See Pics

[Grovenor]

Knobs are a problem,

The place that sells the switches will also sell a huge range of knobs including traditional pointers, just check they are for the correct shaft diameter.

 the shafts need shortening on most switches

A simple job with a hacksaw.

Regards

[Grimberian]

Would I be right in saying that if I am using common return, then on the diagrams that David posted, I wouldnt need all the blue connections, as these would be handled by the return?

[Penlan]

Would I be right in saying that if I am using common return, then on the diagrams that David posted, I wouldnt need all the blue connections, as these would be handled by the return?

Yes.

[APOLLO]

 

When using rotary switches with more than two ways and centre off you can have the issue when selecting a controller that the switch has to pass through the position of a controller that is controlling another section where a train is running and you will get a momentary surge of power, so think about using a separate toggle switch for 'off' and just using the rotary switch to select the controller.

 

That is true for switches that "Make before break".

 

The Maplin switches are "Break before make" (according to their spec) so should be OK, (that is they break contact before making the new contact when operated).

 

DavidCBroads diagrams above explain better than my words !!.

 

Brit15

[Suzie]

That is true for switches that "Make before break"...

 

Brit15

 

The type of switch is irrelevant. If you have to turn the switch from an off position say, via controller 1 to controller 2 - the track will be powered from controller 1 momentarily as the switch is turned.

[BR60103]

Over here. most of the rotary switches seem to have 12 contacts around the outside giving 1-12, 2-6, 3-4.  I've never seen a 4-3.

And passing through a controller that's turned on does cause a jump.

[34theletterbetweenB&D]

... I have decided 5 sections ...

 Not really what you are asking about, but that's not very many at all with three controllers, unless one of them is the single supply to 'N' roads in a fiddle yard, of which only one will be powered by a mechanical arrangment when it is alligned to the layout.

 

The suggested rule in design proposed to me by 'who knows whom in the long ago' was at least three sections per controller, plus a couple extra, so eleven sections minimum for a three controller set up. This delivers nicely flexible operational potential, always somewhere handy to isolate one loco while another moved nearby.

[Pete the Elaner]

Don't go for more poles just to reduce the number of switch positions. I wired up a layout without common return using rotaries for controller selection & used 2 pole 6 way switches. I had 'off' positions between each 'on' position.

'Make before break' or 'break before make' became irrelevant & I was always only 1 stop away from neutral. I found this useful because you will always be able to isolate a section without having to potentially rotate the switch through a position which is live.

[DCB]

Over here. most of the rotary switches seem to have 12 contacts around the outside giving 1-12, 2-6, 3-4.  I've never seen a 4-3.

And passing through a controller that's turned on does cause a jump.

Maplin do 3-4 and 4-3.  You can get multiple deck units giving up to 12 way 6 pole if you look round  

 

 

The suggested rule in design proposed to me by 'who knows whom in the long ago' was at least three sections per controller, plus a couple extra, so eleven sections minimum for a three controller set up. This delivers nicely flexible operational potential, always somewhere handy to isolate one loco while another moved nearby.

Sections per controller is looking at it the wrong way.  You should have the controllers where you want to control from, not all together, One at the terminus, one at the loco depot. one at the hidden sidings etc and use the most convenient one to drive the train.   I drive to the Branch terminus on the Branch controller and back on the Junction station Up side controller(B), or hidden siding controller. (D)  Any one of 4 controllers can operate the branch. Hidden sidings, Up and down main or branch.  You can't see the Branch terminus from the B or D controller nor the junction or HS from the branch. You probably have to group the section switches together though it is not really necessary.  But the principle should be you drive the train from departure to arrival on a single controller rather than "Handing over" Hence "Cab Control." 

[Maxwill]

Don't forget to buy the correct switches ie break before make or make before break. It could make a difference.

[AdamsRadial]

I bought some 6-position switches from Maplins, and discovered that there is a small washer with a bent up tab that acts as the stop position, lifting it, moving it 2 positions around and popping it back in gave me the 4-way switch I was actually after. Remove the panel securing nut and you should see the washer, the bent-up tab goes into the body of the switch.

[Penlan]

I've never really understood under what circumstances one would need a 'make before break' switch,
but I'm sure I will be told soon enough.

 

Agree with one of the posts above where it mentions there is / could be a problem going from position say 1 to 3, as you would briefly contact 2, which if 2's powering another loco somewhere, it would result in a momentary burst of power to the section your trying to connect controller 3 to.

[Grimberian]

Thanks folks, I will make sure there is a switch in there that will cut any power until it is in the correct position.  I am thinking maybe a simple push switch would do the job easily enough; hold button down, twist the switch, release the button to put the power back on?

[Suzie]

That will work, push to break or changeover switches are not as common so you might have to look around to find one.

[Penlan]

It may, or may not, help to look at the type of operations Grimberian is looking to do..

http://www.rmweb.co.uk/community/index.php?/topic/106782-docks-and-holidays-first-layout/&do=findComment&comment=2153657

[Grimberian]

Thanks Penlan, that was going to be my next post this morning.

Here is an up to date photo with my track laid out (not yet pinned or glued).

 

The plan is proable less to do with passenger carriages now, although a couple still scooting aruond the edges will happen occasionally, but more about goods coming and going round both loops, some will go into the sidings (from both outer loops) and some will keep disappearing behind the scenic break and skip the goods yard.  It would be nice to be controlling the goods yard while other trains are on the outer track.  At this point, and operationally, it would be quite simple, but I am more than happy to wire in more sections at this point and not really use them so much rather than wish I had more sections later.

 

Let me know what you think,

(apologies for upside down photo, I have tried rotating and rescaling a number of times to no effect!)

Cheers

Paul

 

 

 

 

 

 

[kevinlms]

 

Let me know what you think,

(apologies for upside down photo, I have tried rotating and rescaling a number of times to no effect!)

Cheers

Paul

It looks fine in Oz!

 

Its just that S3dAOH_l_33Ï) poster that's wrong!