Wiring turntable whisker tracks

I agree that is way too much to spend. How many tracks will you have? You need a SP(n)T, with n being the number of tracks. The concept of rotary to select and toggle to power seems sound.

 

This might work.

Look at Eric's trains blog. He just did this. He is a sponsor!

Thanks for the quick replies - I just posed the question to Eric via FB - thanks for the suggestion since the videos of his recently installation triggered me to consider the TT.

 

Also, many thanks for the  rotary switch link - certainly more cost effective than Graingers at $86!  I plan to install about 10 tracks, so that should fit the bill.

If you use a rotary switch, you're limited to having only one track powered at a time. Not a limitation I would want to have on ours. All of our tracks are wired through their own on/off toggle.

I did the same......just a bit easier to keep track of whats going on.

-Pete

 

Laidoffsick's description of having the option for more than one live track is one I had not thought of - I can imagine scenarios where more then one is live at a time.

 

Dale H, the plan is to provide 18v AC track power to about 10 different tracks around the turntable.  The bridge of the TT will remain live.

 

 

Pete, I like your square pushbuttons with numbers - makes it easy to know which track(s) is powered.

 

Thanks!

Hi Dale,

 

The turntable bridge track remains live and being a 3 rail turntable, continuity isn't and issue. Whatever track power that supplies Gregg's layout tracks with his DCS & Legacy signals gets hooked up to the power wires feeding the turntable bridge track. So it will also carry the DCS and Legacy signals. The auto indexing is controlled either by the keypad for the system or by the Legacy cab2 or cab 1 remote. Hope this helps.

P.S. I like the way Laidoffsick powered his whisker tracks.

 

Pete's turntable above is a manual version where you line up by eye the whisker tracks using the DC transformer (Railpower 1300) and he is using rocker switches to power his tracks.

I order my rotary switch from www.digikey.com it has 12 positions the # is HS16-1SH-ND & the handle # 306-2365-ND it is rated 125v & 15amps it cost about $23.00 plus shipping & handling ,and it looks like the one from grainger .

 

Guy 

Very interesting post.

Picking up on Dale's point, relays to switch power (and TMCC/DCS command signals) closer to their point-of-use is another option.

 

If the control panel is a long-distance (whatever that means) from the Roundhouse, then the switches must be capable of handling the Amps of current.  In general there are more switch styles/options at lower-currents and are physically smaller which can free up precious panel space.  The wiring from panel to RH has to carry the hi-current too which means thicker wiring bundles.

 

If relays are placed near the RH, the hi-current and command signal only travels a shorter distance.  I have no experience with RH and DCS-wiring, but based on what I read here on OGR, it seems shorter/simpler DCS wiring is works better.

 

The key are the relay modules (w/ 10 Amp contacts) on eBay which run about $1 per channel shipped (from Asia).  It's hard to believe the price considering they even have screw terminals.  These modules come in 1, 2, 4, or 8 channels (for example, search eBay for "4 channel 12V relay module").  There are some wiring issues such as providing a 12V power-supply. 

 

Just another option to consider...

 

Remember Im an idiot when it comes to electrical stuff, but what is the benefit from using relays instead of simple SPST on/off toggles. What exactly does the relay do that the toggles won't do?

The main advantage to using relays to switch engine power is that the relay coil uses less than 1/10th of an amp. This allows use of 22 or 24 gauge wire from the control panel switch, instead of 18/16 gauge wire that would be necessary to power the engines. you cannot assume that the TT controls will be within a few feet of the TT/roundhouse--- voltage drop could be severe-- and 10 amp relays are relativly cheap.

Using relays on this project seems like a huge can of worms to be opening for questionable benefit. Now you need a power supply for the coils.

 

I also don't see why anyone would ever need 10A on a turntable track. To draw 10A, one would have to have 2 PW dual motor F3's on the same track. Modern equipment, 2A would probably do the job. We are talking about low speed and virtually no load.

 

Then there's the matter of needing to power more than one track at a time. As long as all of the access tracks that connect to the rest of your world are always powered, and I can't think of a reason why they shouldn't be, and the bridge is always powered, you should only ever need one whisker track powered at a time. I guess there is one potential situation where it might be nice to power two tracks. If you had a full length whisker directly across from a roundhouse stall, and you just wanted to cross the bridge in one move instead of two.

 

Gregg, I still think your original solution is elegantly simple and very practical. The one potential pitfall I see is if the rotary contacts have a low rating, and you don't turn the power off with the toggle first, you could burn them up with arcing.

 

 

The controls will be about 15 feet from the turntable.  However, by the time the power feeds _reach_ the turntable, it's travelled thru 50 feet of 14 gauge wire.  At the farthest reaches of this 24' x 28' layout, voltage drop is 1/2v and DCS signal at 7.

 

I did consider these relays which plug-n-play with these low voltage touch toggles.  I first learned of the Berrett Hill site from Joey Ricard's posts here on the forum.  Again, a bit of an investment for the relay modules, especially for 10 tracks.  But, very cool nonetheless  

Don't get me wrong Dale, I have nothing against relays. I own a couple hundred and plan to use a bunch of them on my current layout.

 

I used to have tons of fun with them on my portable layout at train shows. I made conventional trains do all kinds of "tricks" and wowed the crowds.

 

I just think that for this particular project it adds a layer of complexity that could be avoided easily enough.

If you skip to the 5 minute mark of this video, you'll see why I elected to put toggles on all the whisker tracks. Eventually I can power multiple engines for some cool photo/video sessions. Can't do that with a rotary switch!

 

 

 

I used toggles rated at 6 amps, and haven't had any issues. The tracks are only 2'-4' long, and hold 1 engine at a time. They can be controlled by DCS, TMCC/Legacy, or conventional if needed, without changing anything but a couple buttons on the DCS remote or the Cab 1/2 remote. It's simple, and it works well.

I can see advantages and disadvantages to both methods.

 

Option, To reduce Big wire runs fromt he control panel, the Rotary switch can go to Relays at the TT area to energise tracks.

 

Dale, I think you missed that he wants a SPST switch in series with the rotary sw. That way he is not powering the ones he passes to get to the whisker desired. SPST sw off, rotate, SPST on, Engine powers up on that whisker only.

 

I must say I see no reason to power more than one whisker at a time. A run by track and the Feed from the main line should always be powered.

Also, if there is a Prep track/whisker that needs power part time you can always add a toggle / relay on that track, independent of the rotary switch, even in parallel.

One reason I would think of being able to power all or any of the whisker tracks at the same time would be for photos. If I was taking photos of my TT & Roundhouse area I would want my engines to be lit and probably having their smoke units running.

The relay method also opens the door to remote-control or automated operations.

 

In this thread member Ingeniero has an AIU hooked up to an 8-channel eBay relay module.  He shows a side-by-side on how these multi-channel relay modules can reduce wiring clutter.  $1 per relay for 10 Amp contacts.

Lights, smoke, battery charging, are great reasons to power more than 1 track at a time. I would never want to be limited to 1 track, but that's just me.

 

Besides, even if you run 50' of 14 gauge wire for each track, how much voltage drop are you really going to have? On a 24" up to maybe a 48" or 60" piece of track for 1 engine. Even an old, poorly maintained postwar engine would only draw 4-5 amps max.

 

Why make it more complicated than it really is. If you need 10 amps on a short piece of track for 1 engine, I think you have other problems you might want to look into.  

All the wiring now for the layout is 14 gauge and I'm running 3 posts off a ZW-L.  Have not experienced any problems to date.  Although there may be voltage drop, it has not had any adverse impact in the command control environment (nor with limited conventional running, which was a Thomas - not something known for fine low speed control <g>.

 

Russell is spot on with the notion of the toggle preventing the momentary contacts on the rotary switch from arcing as it's rotated.

 

However, I think the toggles are the best approach for me in this circumstance - easy to hook up, reasonably cheap and multiple tracks can be powered simultaneously.  Thanks for everyone's input - great info from a great forum!

Glad it worked out for you, I felt that the toggle was the best way to go also.  Besides, multiple rocker switches on the layout look cool!

Gregg;

Just so you know I am Good with either way:

I ran toggle switches to all the sidings on my old layout.

And I often had more than one on at a time.

 

And Al;

I had not considered the Photo Op, VERY good point.

Thats part of the fun in this hobby for me, creating the scenes and shooting photo and videos.

I have 23-off position rotary switch that i think got from one of the turntable suppliers as I have 23 spurs.

The spurs are wired so that they can be used as isolated tracks to better program DCS controlled engines.