Hornby DCC Accessory Decoder

[Skier]

Hi

I am just in the process of starting to set up my point motors and linking them to the Hornby Accessory Decoder.

I have linked the Accessory Decoder to my programming track and have set it to 513 which I gather sets all four outputs up for seperate control.  I have then assigned the first output as number 1 which I gather then sets the other inputs as 2,3 and 4.

How do I then set up a point on the layout to work off the decoder?  The instructions seem to indicate that after I have done the first two steps you can connect the decoder to the layout proper.  However, the instructions then seem to say you need to connext the decoder back to the programming track to program the individual points.

I'm afraid I am now at a loss here - please can someone help me with the steps needed to get this connected up correctly.

Many thanks

[Skier]

Hi

Sorry forgot to mention that - Hornby Elite on Firmware 1.45.

Regards

[Chrissaf]

Out of the box, the R8247 is already configured 'ready to go' to operate four Solenoid points using DCC Addresses 1 to 4 without any further configuration required. Thus the steps you have followed so far may have been completely unnecessary.

 

However, the instructions then seem to say you need to connect the decoder back to the programming track to program the individual points. I'm afraid I am now at a loss here

 

I have had a quick look at the R8247 manual, I cannot see anywhere where the manual suggests further port configuration is required after completing the address configuration task.

 

I believe that you have read and followed the section titled 'Simple Addressing'. Then continued to read the next 'Advanced Addressing' section. Probably thinking that this section of the manual needs to be followed as well .... this is not so.

 

You only need to follow the 'Simple' instructions for a basic setup.

 

Once you have successfully configured the DCC Addresses, then just connect the R8247 back onto the Elite 'TRACK A&B' output, wire up your Solenoid '3 wire' point motors to the four output ports of the R8247 and test using the configured DCC Addresses with your Elite [page 57 of the Elite manual].

 

The 'Advanced' configuration is totally optional for those who want to amend the default operating settings to change the length of the 'output pulse' or make it 'always on' for dual aspect signals. The default pulse that the 'Simple Addressing' uses as its default is a pulse length of 100 ms which is fine for most Solenoid point motors.

 

I have linked the Accessory Decoder to my programming track and have set it to 513 which I gather sets all four outputs up for separate control.  I have then assigned the first output as number 1 which I gather then sets the other outputs as 2, 3 and 4.

 

Just a point of clarity. CV513 is the CV to set a 'Group Address'. if you write the value 1 to CV513, then the four ports are addressed as 1 to 4. The value 1 is actually Group 1 not DCC Address 1 ... there is a difference.

 

But if you write a value 2 to CV513 then this is Group 2 which is actually port DCC Addresses 5 to 8.

 

This is all explained in the R8247 manual.

[96RAF]

Accessory decoders work using Group Addresses, which in turn allocate sequential port addresses. Hence Gp 1 equates to ports 1, 2, 3 & 4. gp 2 equates to ports 5 through 8, and so on.

 

The Elite however is smart enough to convert back and forth between Gp and port address and put them in the correct CVs for you. The only time you need to fret about CV513 is if you have an enormous number of accessory decoders on your layout.

 

As Chris says just use the simple addressing method by connecting each R8247 in turn to the Elite Prog terminals and writing the required address, then on to the next module...

 

All that then remains is to connect the R8247 A-B terminals to your track or power bus and a solenoid point motor to each port  (+ C -) noting different makes of point motor use the same colour wires but connected in a different order, just to confuse folk. Note also that + and - marked on the ports are not pos and neg but this way < and that way > . The actual positive is the C terminal. Confused now ?

 

[Skier]

Hi

Thank you for your responses to my question.

You are correct that I have followed the "Simple Addressing" instructions but I have not progressed any further than this stage so I have not undertaken any of the advanced programming.

In this case am I merely good to wire up the point motors and then follow the Elite instructions to control the point motors?

Also if I want to add another accessory decoder do I follow the same Simple Addressing instructions but call it number 2 so the outputs then become 5,6,7 and 8?

Regards

[96RAF]

Short answer - yes.

Wire up module 1 to the first four motors and test.

Then address module 2 on the Elite Prog terminals as 2, which will allocate ports 5-8, then module 3 as 3 (ports 9-12), etc.

There is a list of group vs port addresses in the Rev 2 expanded instructions. 

[Skier]

Hi All

Many thanks for your help with this.

One final quick question if I may.  I've now had a read of the Elite manual and the piece on the set up of the Accessory Decoder is much clearer.   If I want to reset the decoder do I need to write 8 to CV8 - I can then follow the Elite manual to set it up without going down the road of using the 513 set up method.

Thanks

[96RAF]

Yes - acc decoders reset just like a loco decoder and it can help to set their ducks in a row and check they operate before writing their final address.

 

If you have RM then programming them to port addresses is also dead simple.

[Skier]

Hi All

Quick update - decoder reset and now all working a treat.  Much easier to follow the set up instructions in the Elite Manual.

One thing I did find that others may find useful is that the power connecting clip supplied with the decoder that you use to connect it to the track is not the best.  I actually brought a DCC connector track piece and put it in the layout close to where I have situated the decoder.  I then removed the metal connectors from the link wire, tinned the ends with solder and then inserted them into the track piece sprung terminals. This made for a more reliable power feed to the decoder.  You could of course go the whole belt and braces and solder the wire directly to the track but using the designated track piece is a decent compromise in my experience.

Regards

[96RAF]

Good to hear back that all is well.

A power track is a definite improvement on a power clip, but a soldered connection to a designated programming track is preferred, however with an accessory decoder it is just two wires direct between the controller PROG terminals and the PAD A-B track input connections.