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Discussion Starter #1
ok so I decided to give a try on upgrading a cheap h/o to dcc... what best way to learn on a cheap train?

first lesson learned... TAKE PRE PICS!!!!

i cut wires and while stripping.. this one came out and no clue where it goes. any thoughts? I know pics may not be easy to follow...

atest rso z-75150 2654

20200211_181553_1581463490911.jpg

20200211_181458_1581463519507.jpg
 

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Discussion Starter #2
thinking it actually connects to the light...
got decoder hooked up and not soldered yet..
drives.. surges while driving but its moving.
turns out front white to black
red near motor..both ohm out together so back red wire comes from trucks. so it got red.
1 red near motor got orange and white off motor to grey.

now the light will be fun. its a bulb that slides into a square brass piece. most likely will solder wires to bulb and glue it down.

off to mma.. then hopefully tnight solder.
 

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ok so wired it up and there is surging going on. remove decoder and gone.

well ill solder it in and try and run in dcc tomorrow. hopefully all good.
 

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DC wiring is pretty straightforward -- you have a pickup wire coming from wheels on each rail and connected directly to the motor. In most cases each track wire will also go directly to the headlight bulbs.

So to convert to DCC you disconnect the pickup wires and hook those to the power or track inputs on the DCC decoder, then add new wires from the decoder motor outputs to the loco motor. The new wiring arrangement can provide a chance to greatly improve a loco's performance because a lot of the old locos (especially steamers) had very few wheels actually connected to pick up track power. On steamers I like to connect one pair of trucks to each rail, and where possible also try to connect drives on both sides. As an example, I have a Tyco 0-4-0 that would frequently stall on straight track, but after connecting both sets of drivers and tender trucks as power pickups, it now runs at a crawl even over my turnouts. If you have a chance to connect more wheels in your diesels, you should always take advantage of that.

The lights also present a new opportunity while you're working on your loco. You can convert to LEDs simply by adding an appropriate resistor in series. Warm white works greats for steamers, and cool white is good for anything else (including some newer steamers). You can find bulk packages of 3mm LEDs online for a few dollars, and they should provide specs about the LED including the forward voltage and amperage. Use those numbers in an online resistor calculator, and it will tell you exactly which resistor value to get (and if you can use a 1/8W or 1/4W resistor). Depending on your decoder, you will probably have hookups for both forward and reverse lights, maybe even some others.

Regarding the surging... I think you mentioned in another thread you got a digitrax that supports 1A current draw? Are you sure that's enough? It almost sounds like your loco motor is pulling more current than the decoder can provide.
 

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Discussion Starter #5
DC wiring is pretty straightforward -- you have a pickup wire coming from wheels on each rail and connected directly to the motor. In most cases each track wire will also go directly to the headlight bulbs.

So to convert to DCC you disconnect the pickup wires and hook those to the power or track inputs on the DCC decoder, then add new wires from the decoder motor outputs to the loco motor. The new wiring arrangement can provide a chance to greatly improve a loco's performance because a lot of the old locos (especially steamers) had very few wheels actually connected to pick up track power. On steamers I like to connect one pair of trucks to each rail, and where possible also try to connect drives on both sides. As an example, I have a Tyco 0-4-0 that would frequently stall on straight track, but after connecting both sets of drivers and tender trucks as power pickups, it now runs at a crawl even over my turnouts. If you have a chance to connect more wheels in your diesels, you should always take advantage of that.

The lights also present a new opportunity while you're working on your loco. You can convert to LEDs simply by adding an appropriate resistor in series. Warm white works greats for steamers, and cool white is good for anything else (including some newer steamers). You can find bulk packages of 3mm LEDs online for a few dollars, and they should provide specs about the LED including the forward voltage and amperage. Use those numbers in an online resistor calculator, and it will tell you exactly which resistor value to get (and if you can use a 1/8W or 1/4W resistor). Depending on your decoder, you will probably have hookups for both forward and reverse lights, maybe even some others.

Regarding the surging... I think you mentioned in another thread you got a digitrax that supports 1A current draw? Are you sure that's enough? It almost sounds like your loco motor is pulling more current than the decoder can provide.
some good points there..

on the lights. yes convert to LED would be good. Ill do that another day.. hah..
right now I took a light out of an old tyco santa fe to use on the rear of this guy. will get it all wired in and see how that goes.

hmm on the 1A.. you maybe right. so the decoder may need to be a bigger one then. didnt think of that.
will look more into that.

thx!!!!


wont get to it tonight most likely. Got salsa class with wife from 7:15pm to 8pm... our MMA Coach got an instructor for V-Day... so gonna be fun, then MMA class from 8pm-9pm... home by 9:30.. doubt any time to play tonight. but tomorrow I will definitely.
 

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It would be very unusual for a loco to draw more
than .4 or .5 amps, most are much less. First thing to
do is find out what your loco is drawing. Disconnect
one wire to your track. Set your multimeter for
AMPS. Connect one probe to the track, the other
to the disconnected DCC wire. Run the loco and
note the meter reading. Let us know the reading.
If near 1 amp you possibly have old inefficient
motor which would require a decoder permitting
higher draw than 1 amp or replacement of motor.

The 'surging' could possibly be caused by friction
in the gear train. Clean the trucks and relube with
plastic friendly 'grease'. Check for binding.

Don
 

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Discussion Starter #7
train runs perfect without decoder in.
I removed the decoder and got the amp reading... .35 max from a dead stop to full power and .21 running around track in full throttle.

I believe this is going to be my rushing into things fault. i hooked back up the decoder to check amps. while it moved and surged... then stopped and wouldnt... I pinched a wire and it took off as i had the throttle maxed.

so i need to sit back and solder and clean it up. get it in then test...lesson learn #2. i twisted wires tight but guess not enough for a quick test on track.

so lessons learned
#1 pics of wires before starting
#2 solder it all together then test
 

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Are you sure the motor connections (brushes) are isolated from the frame? before connecting the decoder check with an ohm meter that the brushes (motor connections) are are not connected to the rail power or the frame! Old BlueBox Locos have hidden tab under the motor that connects it to the frame that needs to be removed.
 

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Discussion Starter #9
Are you sure the motor connections (brushes) are isolated from the frame? before connecting the decoder check with an ohm meter that the brushes (motor connections) are are not connected to the rail power or the frame! Old BlueBox Locos have hidden tab under the motor that connects it to the frame that needs to be removed.
I didn't do that and have it running now. Only problem is I have it where the train is running in opposite direction than it is supposed to be. I was told reverse the wires but then that doesn't follow the instructions...
 

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The motor on your loco is DC. So if it is running
the wrong direction, you probably connected the
wires from the decoder to the motor backward.
Flip them. The wires from the trucks to the
decoder are AC so
it wouldn't affect direction no matter which way they were connected...however
it is recommended that red wire goes to right rail wheels and black to the left rail wheels.

If that does not resolve the situation you may have
somehow reset the decoder.

Does headlight burn when loco is actually moving
forward when the controller is set for REV?
If so, then consult the DCC system
manual for directions in changing the Forward and
Reverse in the decoder to match the FW REV on
the controller.

Don
 

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Didn't you say some of the wires fell off and you replaced others? How are you trying to follow directions for color-coded wires if you don't know what colors were originally connected to what locations?
 

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Riggzie wrote:
"Only problem is I have it where the train is running in opposite direction than it is supposed to be. I was told reverse the wires but then that doesn't follow the instructions..."

You can re-program the decoder to compensate for this, and the loco will run in the right direction.

If you have JMRI, there's an easy toggle for it.
 
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