Greetings,
I have a brass 0-10-0 switcher that I would like to convert to DCC. Originally, there was a single wire that connected the (+) motor brush to the motor mount, which I replaced with separate color-coded wires:
The right drivers are shorted to the frame & motor bracket and the (-) motor brush connects to the insulated nut above the drawbar, that shorts to the left (fireman side) wheels of the tender.
To properly isolate the motor brushes from the frame, the orange wire would be soldered to the (+) motor pad of the decoder and the grey wire to the (-) motor pad of the decoder. I would still need to use the frame or chassis to solder the red wire to the right rail pad of the decoder and the black wire from the decoder would be soldered to the isolated nut above the drawbar, which picks up power from the left wheels of the tender.
Am I correct to presume that the decoder would then be isolated properly and safe from letting out the magic smoke - in the event of a short?
Actually, I will need to fit the decoder in the tender. So I'll need add a single contact connector so that I can easily separate the tender from the locomotive, if needed.
Thanks for the input...
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Hi there. Make sure that your motor is isolated from frame. Did you secure it with silicone? Also make sure that the decoder is properly protected. You should test it on your programming track...
Simon
If the decoder is in the tender you are going to have more than one wire with a plug. A red wire hooked to the loco frame, orange to the + on the motor, gray to the - on the motor, white to the H/L.
You can power up the H/L via wire from the frame. If the H/L is a Led the wire coming from the frame will be your + to the LED. DON’T FORGET A RESISTOR. No need for a black wire going to the loco has the left rail pick up is in the tender.
snjroy Hi there. Make sure that your motor is isolated from frame. Did you secure it with silicone? Also make sure that the decoder is properly protected. You should test it on your programming track... Simon
For most motors (the one in the above 0-10-0 for one, I believe), the outside "shell" is electrically isolated. So you don't need to insulate it from its mount. For example, I built a loco with a Kato motor clamped by a brass assembly.
With older motors set up like the Pittmans, the factory tended to electrically connect one brush to the motor "shell". It is usually simple to disconnect, thus turning it, electrically, into the motor described in the previous paragraph.
The safest thing to do is to test my assertion on your own motor: get your VOM out, and see if there is continuity between each brush and the motor frame.
Ed
This is what happens when you try to think about these things later at night.
Yes, with the decoder in the tender, there will definitely be more than one wire going to it from the locomotive: 5 total
I have some header connectors to use for that - like the ones pictured in Mel's post. Or, I may purchase one of the commerically available flexible cable connectors. I will also be adding front and rear headlights but didn't mention that because the thrust of the thread was about a properly isolated motor.
For some clarification: BOTH the (-) and (+) motor brushes are completely isolated from the frame. The motor housing (or shell, as Ed refers to it) is mostly* isolated from the frame.
*[NOTE: I can occasionally find small points that show continuity between the two but I have to really probe for them. I'm guessing that this might be due to minute openings in the paint layer on the outside of the motor housing?]
Again, neither of the motor brushes show continuity to the frame. So I don't see a need to isolate the motor bracket from the frame.
It doesn't matter whether there is continuity between the motor shell/frame and the frame of the locomotive. IF. The brushes are isolated from the shell/frame.
Which is how we do it, these days.
7j43kIt doesn't matter whether there is continuity between the motor shell/frame and the frame of the locomotive. IF. The brushes are isolated from the shell/frame.
And they are. Thanks for re-confirming that, Ed.
One of the gurus here took me to task seven or eight years ago when I posted that the motor must be isolated from the frame. He urged me to be more specific and only to tell people that the brushes are what must really be isolated. Either way, it seems to me that if you have a power metering intermediary, i.e. the decoder, all wires should run back to it.
-Crandell
selectorOne of the gurus here took me to task seven or eight years ago when I posted that the motor must be isolated from the frame. He urged me to be more specific and only to tell people that the brushes are what must really be isolated.
I think I got a similar "pep talk" by the same person for the same reasons, Crandell. Always something to learn...
So long as you never get continuity from the + or - motor terminals to the loco frame, you are good. Random blips betrween the motor body and the loco frame is ok. Even minute random blips between the terminals on the motor and the loco frame spell dead decoder at some point.
Since youi have it all apart anyway, consider adding some wheel wipers to pick up from the other side of the loco and pass 6 wires back. Likewise add wipers to the non-pickup side of the tender. It'll run like a dream.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks, Randy. Do you have particular brand of wheel wipers you prefer?
Good luck Tom.
.
My collection of brass steamers is the only reason that I will never convert to DCC. I do not need that much work to do.
-Kevin
Living the dream.
Kevin,
I've converted one brass locomotive to DCC so far: An Alco Models H20-44. Although not as complicated as a steamer, it actually turned into an enjoyable mind-puzzle to figure out where best to place the Loksound decoder and speaker. Simplicity turned out to be the operative word, as the solution was easier than my first expectations. Even so, I found it a good and encouraging learning experience that I hope will dictate how to tackle other projects - even steamers - in the future.
So, don't let brass deter you from enjoying the advantages of DCC - i.e. if that's the ONLY thing keeping you from making the switch. The three brass steamers I have all have can motors, which makes converting them easier electrically. I also look at it as an ongoing project, which I'm in no hurry to complete.
I enjoyed running (and breaking-in) my brass 0-6-0 switcher around the imaginary Christmas tree this year. Before the track gets packed up I'm hoping to also thoroughly break-in the 0-10-0 prior to installing a decoder into it. Given that it will go into the tender, I can convert it for now using a motor-only decoder then add sound - if I choose - when funds are more readily available.
Tom,
Instead of the added wipers, you might want to install a "keep-alive", instead.
My favorite is the ESU, as you can still program on the program track. If you went with a different brand, a disconnect switch for the "keep-alive" would be in order.
Thanks, Ed. The keep-alive cap did cross my mind after I posted last night. There should be ample room in the tender.
I really like Loksound decoders but their steam files are still pretty limited as far as Amercian steam goes. I may go with a TCS Wow for my 0-10-0 and 0-6-0 so I can opt for a prototype NYC whistle and chuff. Do you know if there are programming issues when using a TCS Wow with a TCS keep-alive?
tstageDo you know if there are programming issues when using a TCS Wow with a TCS keep-alive?
Yes
I have found when using NCE 5amp system, the keep alive causes issues on the programming track.
Two work arounds:
Program before plugging in the keep alive the first time to final test installation.
If you are highly confident in your decoder installation, you can place in on the main and allow the decoder to charge, then move it over to the programming track. I have done this once or twice. I do not believe this will harm the command station in any way.
You can also POM if you dont have anything else on the track.
tstage Do you know if there are programming issues when using a TCS Wow with a TCS keep-alive?
Do you know if there are programming issues when using a TCS Wow with a TCS keep-alive?
You can put a teeny little switch on the bottom of the tender. A simple on-off (might be better to use a two-pole, to disconnect BOTH leads). One (or two) of the wires to the "keep-alive" then goes through that switch. When it's switched off, you should be able to program on the program track.
I put a "keep-alive" in a gas-electric (which REALLY needed it!). It was an all-Soundtraxx install. For whatever reason, I didn't put "the switch" in. I found that I could Program on the Main. Very easily. BUT. You have to keep really good records, because you can't query the decoder. So if you change a CV, you darn well better write it down. On that gas-electric, I changed LOTS of CV's. And wrote them all down. And have them in a file, should I need them.
So, programming on the main is not the end of the world. But it's nice not to HAVE to do it.
Hence, the switch recommendation.
7j43k tstage Do you know if there are programming issues when using a TCS Wow with a TCS keep-alive? You can put a teeny little switch on the bottom of the tender. A simple on-off (might be better to use a two-pole, to disconnect BOTH leads). One (or two) of the wires to the "keep-alive" then goes through that switch. When it's switched off, you should be able to program on the program track. I put a "keep-alive" in a gas-electric (which REALLY needed it!). It was an all-Soundtraxx install. For whatever reason, I didn't put "the switch" in. I found that I could Program on the Main. Very easily. BUT. You have to keep really good records, because you can't query the decoder. So if you change a CV, you darn well better write it down. On that gas-electric, I changed LOTS of CV's. And wrote them all down. And have them in a file, should I need them. So, programming on the main is not the end of the world. But it's nice not to HAVE to do it. Hence, the switch recommendation. Ed
This is a better idea.
I have done a bunch of brass decoder installs, both for myself and others. In fact, I just did a Overland LV "John Wilkes" 4-6-2 for a friend, adding a LokSound and a keep-alive to it, and used an iPhone4 speaker. It works great.
The secret to programming and reading keep-alive equipped locos on a programming track is to have a programming track that can be switched quickly to a mainline track with the flick of a DPDT toggle.
Put the loco on the track and move the switch to "mainline". This will charge the cap. Get your throttle into program mode (page mode on a Digitrax throttle), and select the CV you wish to set, then select the variable. With your finger on the "ENTER" button, switch the DPDT toggle from "mainline" to "program" and immediately hit the "ENTER" button. The decoder will take the CV.
To read it, do the same thing. Charge the cap on "mainline", get the throttle into program mode, select the CV but leave the "???" displayed (on a DT400). With your finger on "ENTER", switch the toggle to "program" and hit the button. The decoder will be able to be read (if you have a Zephyr or Chief).
You must do this every time you set or read each CV. The cap will discharge between CV's otherwise. A bit of a pain if you're doing a lot of CV's, but then you don't have to add a mini-switch to your engine either.
Crandell and tstage, That was probably me that pointed out the difference between isolating a motor from the frame and isolating the brushes from the frame.
It all dates back to a fellow club member of mine who tackled his first steam engine install using an old HOn3 steamer (MDC, I think). Anyways, I told him to isolate the motor from the frame. And he did, all right. He fabricated a total and complete plastic styrene motor housing to hold the motor in place, which took him hours to design and build.
But all he really had to do was unsolder the wire from the frame to the motor brush. Sigh. He did nice work, but totally not needed.
Paul3Crandell and tstage, Whistling That was probably me that pointed out the difference between isolating a motor from the frame and isolating the brushes from the frame.
No offense taken, Paul. I appreciated the correction.
Paul3 You must do this every time you set or read each CV. The cap will discharge between CV's otherwise. A bit of a pain if you're doing a lot of CV's, but then you don't have to add a mini-switch to your engine either.
But if you program on the main, you can set the CV's rather more directly.
When I did mine, I only wrote down the ones I changed. Because if I'm happy with the others, I don't need to know them. And then I didn't have to read any CV's at all.