Hello all,
I am working to wire DCC to recently installed MicroEngineering Code 70 flex track. I am noticing that the 'short circuit' test is failing unless I place feeders every 16" or so. Even on the same piece of track (between joiners) I need to have two feeders.
My DCC is #14 bus wires with #22 feeders. The bus wires are about 20' from the booster and the feeders are < 6".
This phenomenon is contrary to my experience with Atlas Code 100 flex track. In that case I was able to place feeders over 8' apart and still have the wiring pass the short-circuit test.
Has anyone else noticed excessive Vdrop with MS code 70? Can you share your experience with wiring DCC to MS code 70 track.
Thanks in advance.Dwayne A
Dwayne
I have no experience with the MS rail but that should not matter. I am building with ME rail in code 55, 70 and 83. Is this rail weathered or coated with something? Do you have good solder joints? Does shorting across the buss shut the booster down? Track code should not matter when it comes to buss wiring.
At least its good your testing.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
Hey Pete,
My bad - it's Micro Engineering track, (don't know where the heck I got Micro Scale from...)
The track is non-weathered.
My soldering is pretty solid - years as an electronics tech did yield some skills.
Shorting the bus does shut-down the booster.
More work is showing that as feeders are added the reliability is increasing, but I'm still ending up with one feeder per section of track even though the track is soldered at both ends.
D
Try a section of track with #18 feeder wires and see if it makes a difference. Any way the size of the rail should not matter. On my portable modules with all code 100 track I did feeders on every rail for reliability due to the abuse they go through. My home layout is code 55,70 and 83 and is soldered every 6 feet or so. Is your track ballasted yet? Try a bright boy and clean the track. Maybe there is some non conductive coating on it.
Just a thought:
How much smaller in cross-section is the code 70 compared to the code 100? I have a feeling the code 70 just conducts less power than the code 100, requiring more frequent feeders.
I don't think 18 gauge feeders would help anything. Might be bigger than the code 70 rail itself. I put a whole bunch of 18 ga. feeders on the club layout, code 100, and it was a bit difficult due to the large size of the feeder compared to the rail. Won't be doing that again. 20 ga. or smaller for feeders next time.
Mike WSOR engineer | HO scale since 1988 | Visit our club www.WCGandyDancers.com
I don't think it is the track that is causing your problem. Myself and my buddies use ME code 70 flex and DCC. We don't have the problems you are describing. I use 22/24 AWG feeders to every track section that is not soldered to a piece with a feeder.. I have measured the voltage drop on my track with a DCC meter, under load - no problem. Before I permanently wired the layout, it was jury rigged with lots of sketchy feeds and very few of them. Still ran well.
Sounds to me like you have a problem with either the buss or possibly dirty track?? Being an electrical guy, should be easy for you to track down the source. Things like this can be discouraging. Good luck with the trouble shooting.
Guy
see stuff at: the Willoughby Line Site
Hey thanks for all the feedback, guys.
Turns out 'twas a combination of two bad connections; one on a bus wire at the booster, and one bad solder joint on a rail.
Once I got those fixed I got pretty predictable results on the short-curcuit test. I found I could reliably shut-down the booster 8-10 track feet from the last feeder. To ensure solid operation I moved the next feeder in about 2 feet from that point. End result is that there are feeders about every 5-6 feet. (All track joints are soldered.)
Goes to show the value of ongoing testing as feeders are being installed.
Keep your stick on the ice.D