Select control issues

[josh_swales]

Hi,

I was brought a Select in May from a retailer to control a small shunting layout. Initially it was fine however in the past few weeks it has developed a fault where for no apparent reason whichever engine I have on track doesn't respond and seems to develop a mind of its own- speeding up for no reason and continuing to move after they have stopped with the dial still set to 0. The two locos I use on this layout both have Zimo decoders in them. I have reset both chips and reset the controller as per the instructions however the problem persists.

The select is running the latest firmware. Does anyone have any experience of this issue?

[96RAF]

As you recently bought the Select from a retailer we presume it was new and has the latest firmware - i.e it shows 20-30-03 at power up. If it is the pre-facelift model it will show 16-30-03 which functionally is exactly the same.

If you see the initial number as 15 or less then your Select is not at the latest revision.

 

What you are describing is DC runaway and occurs if the decoder has DC running enabled in CV29. The latest revision of Select defaults to DC running disabled in the controller, which helps, but you need to check each decoder has DC running disabled as well.

 

As the Select cannot read CV values, your only option is to write a suitable value to the CV.

 

This calculator will help find the correct value taking account of any other settings you require.

http://www.2mm.org.uk/articles/cv29%20calculator.htm

 

One other thing to look at is your power connection to the track. If it is a commercial clip or power track check to see if it is for digitsl use. If a DC version then you can simply clip out the capacitor. The capacitor disrupt the DCC signal.  If your power feeds are soldered direct to the track then this does not apply.

[josh_swales]

As you recently bought the Select from a retailer we presume it was new and has the latest firmware - i.e it shows 20-30-03 at power up. If it is the pre-facelift model it will show 16-30-03 which functionally is exactly the same.

If you see the initial number as 15 or less then your Select is not at the latest revision.

 

What you are describing is DC runaway and occurs if the decoder has DC running enabled in CV29. The latest revision of Select defaults to DC running disabled in the controller, which helps, but you need to check each decoder has DC running disabled as well.

 

As the Select cannot read CV values, your only option is to write a suitable value to the CV.

 

This calculator will help find the correct value taking account of any other settings you require.

http://www.2mm.org.uk/articles/cv29%20calculator.htm

 

One other thing to look at is your power connection to the track. If it is a commercial clip or power track check to see if it is for digitsl use. If a DC version then you can simply clip out the capacitor. The capacitor disrupt the DCC signal.  If your power feeds are soldered direct to the track then this does not apply.

Hi,

 

yes it is definitely running v1.6. I tried reprogramming CV 29 however this had no effect. The track feeds is soldered directly to the rails 

[Chrissaf]

Initially it was fine however in the past few weeks it has developed a fault where for no apparent reason.........

 

With DCC the electrical path between controller and loco decoder has to be spotlessly clean. It only takes a few weeks for a layer of dust [near invisible] to build up, or tarnish [oxidation] to build up on the tops of the rails. Everything looks clean to the eye, but to DCC data this is an insulating barrier that allows data to be lost or corrupted in the transmission path. Once a DCC decoder looses synchronisation of the DCC data it thinks that there is no DCC signal present and switches into 'DC Operation' mode and all DCC control is lost.

 

Assuming that this deduction is correct, you need to thoroughly clean your track. First with a proper track cleaning rubber, then finish off with a cotton rag and IPA [IsoPropyl Alcohol].

 

Many DCC users undertake the IPA part of this cleaning regime at the start of every play session to maximise operational reliability. The IPA removes any dust build up and takes off any grime deposits. The track rubber should be delegated to more severe running issues and used more sparingly.

 

Use IPA and cotton buds on the loco wheel treads and pickup rubbing area [typically but not always the back surface of the wheels].

 

DCC is far more sensitive to electrical track conditions and track cleanliness than DC Analogue ever was.

 

/media/tinymce_upload/31ab770a89364151932207e6da0932d2.gif

TIP: As a newbie poster on the forum, just be aware that the 'Blue Button with the White Arrow' is not a 'Reply to this post' button.

 

If you want to reply to any of the posts, scroll down and write your reply in the reply text box at the bottom of the page and click the Green 'Reply' button.

.

See also – further TIPs on how to get the best user experience from this forum.

https://www.hornby.com/uk-en/forum/tips-on-using-the-forum/

.