turntable on dcc layout

[Fishmanoz]

Disconnect the bridge, use insulation tape, use adapted inlet track or don't use the inlet track at all and just isolate the outlet tracks - many ways to skin a cat.

 

I like Blackbird's isolated inlet track solution myself - the bridge is live and

 

you have to isloate only a minimum of outlet tracks. See it further up this thread.

[GordonBigBoy]

I really would like to get the turntable but the above Blackbird Minoo explanation is difficult to comprehend without physically having TT to hand. I wonder if a simple drawing of the modification could be posted - would be much appreciated.

[GordonBigBoy]

Cancel my last - have now found http://www.brian-lambert.co.uk/DCC.htm#Basics which has TT pictures and diagrams which I can study to try to understand. I now know what a DCC Bus is.... wow this is complex stuff - thought I would just be pushing pieces

 

of track together....

[minoo]

Sorry guys I was not following the post for the last week. I would love to post the photo showing where I have put the insulating tape but can you all guide me. Better still, I could send the photo to some e mail address of you guys.

Awaiting your replies.

minoo

[poliss]

Do you have a Photobucket account minoo? You can upload the photos there and put a link to them on here.

[minoo]

[reply]poliss said:

 

Do you have a Photobucket account minoo? You can upload the photos there and put a link to them on here

 

Dear Poliss,

unfortunately, I do not have any accounts online. I have the photos on my laptop and can gladly send

 

it bt e mail to you to do the needful.

Is there a possibility to attach my photos withthe replies???

minoo

[poliss]

You can't swap email addresses on the forum, nor does the forum allow attachements.

Getting a Photobucket account is easy and free. It's also useful as a back-up if your computer dies, as mine just did. :-(

[YorkieFletch]

Hi all, like many of you out there, have just got back into 'trainset mode' after many years (20+) away. Decided to go for the full monty and go DCC and everything Hornby to minimise any issues. So have wired my board up with all tracks, soldered and dropped

 

wires onto the bus including all sidings from my turntable, which has been fitted with a decoder. Still with me? My loco's have sound so wish to have the pleasure of these engines warming up on their sidings before coming onto the turntable and into play on

 

my loops. 1st attempt was last Friday, I drove my shunter off the loop, onto the inlet track of the turntable, turned it to meet up with its siding and as soon as attempted to leave the turntable, ERROR came up on my Elite controller, obviously a short. Now

 

I have read the threads but the solutions I've seen only appear to indicate having power on when lined up with the track on the turntable. Any quick solutions, or slow ones even? My thought was to to cut the track that clips onto the turntable and put a isolated

 

gap in there (is that what someone produced?, Surely that would be a good solution for Hornby to offer for dcc users or I'm I missing something here?)I would prefer something simple please and not too techy? Also, other problem I had was that my Elite would

 

only operate my points (via Hornby decoder) that I had connected, in one direction, had to manually push it back, any ideas would be welcome?

[Flashbang]

Hi,

Check your siding wiring is correct. A reversed pair of droppers will result in a short when the locos metal wheel bridge the end of the TT and the exit/inlet incorrectly wired track.

 

Next, have carried out the Hornby TT conversion for DCC

 

rail operation by removing the wiper contacts on the TT? Or alternatively if you don't want to rip them off have you fitted Insulated Rail Joiners (IRJs) to all the tracks leading onto the TT?

 

As for point operation and assuming your point accessory

 

decoders are still at their default setting of Pulse output you need to connect the motors wiring as..... Hornby Motor Black wire to C terminal of one block of three connections. Then connect Red and Green motor wires to the same block but onto the + and -

 

terminals. Should the point motor throw the opposite way to that set swap around the red and green wires only.

[YorkieFletch]

Flashbang said:

Hi,
Check your siding wiring is correct. A reversed pair of droppers will result in a short when the locos metal wheel bridge the end of the TT and the exit/inlet incorrectly wired track.

Next, have carried out the

Hornby TT conversion for DCC rail operation by removing the wiper contacts on the TT? Or alternatively if you don't want to rip them off have you fitted Insulated Rail Joiners (IRJs) to all the tracks leading onto the TT?

As for point operation and

assuming your point accessory decoders are still at their default setting of Pulse output you need to connect the motors wiring as..... Hornby Motor Black wire to C terminal of one block of three connections. Then connect Red and Green motor wires to the same

block but onto the + and - terminals. Should the point motor throw the opposite way to that set swap around the red and green wires only.

[YorkieFletch]

Thanks Flashbang for advice, I'm pretty confident that all the wiring is correct. I will get some Isolated Fishplates but wasn't sure that it would provide a sufficient gap to stop the connection between the 2 differing supplies coming into contact especially

 

when the wheels of the engine could remake the joint, if that makes sense! It is at that point when it makes contact between the turntable and my other live sidings that it 'Error's out. I even experimented by trying turning the TT another 180 degrees. I did

 

carry out the Conversion for the TT as per the Hornby Instruction which req'd the removal of the copper plates. As for the points issue, I have not interferred with any settings on the Decoder and only connected 4 points to my 1st decoder, I have another 9

 

points to connect yet so I want to crack it on my 1st 4 before having a major rework. I'll try your motor wiring and advise you of the success or not. Once again, many thanks, really appreciate your help.

[Fishmanoz]

Fishplates isolation should be sufficient. The problem here should only be while the turntable is rotating, not while running a loco.

I suspect you are using an outlet with reverse polarity. See details further up the thread and refer to the Brian

 

lambert link.

 

Your point problem may simply be your point not being flat, and/or the point motor being held down too tightly or being slightly out of alignment. Try some adjusting and see how it goes.

[Blackbird]

Hi YorkieFletch, Your work on the turntable electrical isolation would seem to be correct, whether isolation is by removing the bridge contacts or by track isolating fishplates (track connectors), the isolation will be defeated when a loco spans the isoloated

 

'gap'. When 'designing' the electrical paths, you must take into account that the turntable bridge (mechanically) changes over the 'polarity' of half the outlets, approximately the opposite side to the inlet track.

[YorkieFletch]

Blackbird said:

Hi YorkieFletch, Your work on the turntable electrical isolation would seem to be correct, whether isolation is by removing the bridge contacts or by track isolating fishplates (track connectors), the isolation will be defeated

when a loco spans the isoloated 'gap'. When 'designing' the electrical paths, you must take into account that the turntable bridge (mechanically) changes over the 'polarity' of half the outlets, approximately the opposite side to the inlet track.

[YorkieFletch]

Hi and big thank you. Problems resolved. It turned out that when I 1st tried it out,I just so happened to try the shunter on the half where the polarity changes. So started from inlet and went to each siding going clockwise all ok then hit the 3 sidings

 

that were on opposite polarity, reversed the wiring on those sidings and everything is perfect. Now I can have my sound on in the sidings irrespective of the position of the tt. Also, resolved my points issue, I had wired them incorrectly, I was carried away

 

with red & black being + and/or - ! Senile dementia is popular in my house! All helped to make a good weekend.

Now do you know if it is possible to wire 2 points to one port on a decoder as I have instances when I need to move 2 points at same time?. I'm

 

on Elite and I will soon be on Railmaster eventually but wondered whether it can be done. Cheers & Thanks again

[Flashbang]

Hi

Yes its ok to wire two solenoid point motors to one outlet port. Typically this will be where a cross-over pair of points are to be moved together.

 

If you extend any of the wires ensure you use 16/0.2mm for all three motor connections

 

[YorkieFletch]

Thanks Flashbang. I'm ok with the wiring size that's what I've used on my droppers to my bus wire. In theory then, could I use 8 points ie 4 pairs of crossover points on one decoder or do you have to compensate and leave 1 port empty to compensate for

 

the 2 into 1 port for a crossover situation? By the way, recently purchased Sparrow Hawk, beautiful and great sounds. Highly recommend.

[Spaniard]

Hi all, I am a complete novice with anything like this although if the instructions are set down on paper I can follow instructions to the letter. I have followed the Hornby instructions to convert the t/t pulling out the contacts and wiring a decoder.

 

I now have power to make the table rotate but when my loco reaches the track on the bridge it is dead. I have rechecked all the connections and am satisfied they are right. Can anybody give me a clue on what to do in plain English. Thanks

[Fishmanoz]

Hi Spaniard, welcome to the forums. If you do a search on turntable in this forum, you'll find heaps in here about converting the TT to digital.

 

The power to the bridge comes via two brass connectors that make contact under the inlet track. As

 

long as you have power connected to the inlet track, the bridge should be powered too. Check to ensure they are making contact correctly.

 

What you will have to make sure of is that you have power connected to all of the outlet tracks now that you have

 

removed all the contacts at the ends of the bridge rails. This is one of the unfortunate disadvantages of this method of conversion. Your search of the forum will tell you other ways.