|
|
Post by godzilla on Jan 17, 2020 18:16:52 GMT -8
Need some help. When turning the power on all dcc engines take off at full speed until I turn the throttle up/down, then they settle down into dcc. Then everything runs as it should until I shut it off /on again.
What could be the problem? Wire mistake? Something else
Dave
|
|
|
|
Post by Mark R. on Jan 17, 2020 19:11:38 GMT -8
You should disable the ability of your engines to run on DC. This is accomplished by the settings in CV29. Use this "calculator" to determine the value you should have in CV29 .... www.2mm.org.uk/articles/cv29%20calculator.htmYour will probably want a value of 2 (2-digit address) or 34 (4-digit address). That should stop the run-aways. Mark. |
|
|
|
Post by godzilla on Jan 17, 2020 21:03:27 GMT -8
Never happened before until I changed some of the track. But can't figure out what I did to cause this. Besides I have many older dc only engines that I like to run every now and then.
Thanks Mark for your thoughts, anybody else?
Dave
|
|
|
|
Post by Colin 't Hart on Jan 18, 2020 3:02:41 GMT -8
Never happened before until I changed some of the track. But can't figure out what I did to cause this. Besides I have many older dc only engines that I like to run every now and then. Reprogramming CV29 on your DCC locomotives will not affect your ability to run your "older dc only engines". |
|
|
|
Post by edwardsutorik on Jan 18, 2020 8:22:39 GMT -8
Yes. Mark is probably right. To find out, take all your locos off the layout. Pick one, and do the CV change like he said. It will either be fixed, or it won't. If the former, continue with the CV change. If the latter, try one or two more, and see if the problem continues. If it does, Mark was wrong (as far as his recommendation fixing your problem). And we'll have to kick it around some more. The CV calculator he recommends is REALLY a nice one. I use it so much, I have it bookmarked. And. AFTER changing the CV, re-read the number (again) to CONFIRM it was changed to the correct one. I've had "problems" with that, sometimes. Ed |
|
|
|
Post by canrailfan on Jan 18, 2020 10:46:40 GMT -8
What DCC system are you using? Do your DCC locos each have their own address?
If the problem affects all the locos on your layout simultaneously at power-on, it's unlikely to be a decoder programming issue. Possibly a command station error or the cab bus wiring has a short or broken circuit.
EDIT: Now that I re-read your second post, you say this happened after changing some track. Look carefully to see if you overlooked making a needed gap somewhere, either in the new track or where it connects to the original track. Also check the track feeders for the new track and see if perhaps one is shorting to any non-DCC wiring.
|
|
|
|
Post by jonklein611 on Jan 18, 2020 14:05:26 GMT -8
If you've got multiple boosters, make sure the boosters aren't set into command station mode.
|
|
|
|
Post by godzilla on Jan 18, 2020 18:24:12 GMT -8
Found the problem, it was short from a bad section of track. After replaced it was back to normal. Btw my dcc system is nce and all engines have separate addresses.
Thanks guys for your help,
Dave
|
|
|
|
Post by canrailfan on Jan 18, 2020 20:21:54 GMT -8
That's good news! Glad your trains are running normally again.
|
|
|
|
Post by edwardsutorik on Jan 19, 2020 9:11:30 GMT -8
Found the problem, it was short from a bad section of track. After replaced it was back to normal. Btw my dcc system is nce and all engines have separate addresses. Thanks guys for your help, Dave Weird how there could be a short without tripping a breaker and/or the track voltage going down to near zero. I wonder what the mechanism is where a short makes all the locos run full speed. Ed |
|
|
|
Post by godzilla on Jan 19, 2020 16:38:12 GMT -8
Not sure why it never tripped a breaker but I did find some rust under the track web. Sometimes there is just no reason for what happens, I'm just glad I found the problem.
Dave
|
|
