DC loco runs in reverse when used with DCC System

Started by hawaiiho, January 28, 2009, 02:51:12 PM

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hawaiiho

Quote from: Yampa Bob on January 28, 2009, 08:47:34 PM
A question in my mind is, are the DCC turnouts not wired to be compatible with the add-on DC controller?

Interesting, I have the same question in my mind. Trying to get an answer from Bachmann is nearly as frustrating as the exceedingly poor documentation that they provide.

the Bach-man

Dear Hawaii and Bob,
As I have mentioned elsewhere, the DCC turnouts throw contrary to the symbol on Dynamis. Presumably this will be addressed in future production. I have quickly gotten used to it; I simply push the button not highlighted.
Have fun!
the Bach-man

Yampa Bob

Yes, I remember the comment about the Dynamis, however Hawaii is using EZ Command, not Dynamis.  Is the problem with the turnouts or with Dynamis?

As I read it, the problem is not with direction of throw, but that the turnout is totally inoperative when the track is wired to allow the DC controller direction switch to match direction of travel.

Hawaii,
In lieu of a schematic or troubleshooting guide, I usually resort to taking things apart to either fix or re-engineer the thing.  I have taken regular turnouts apart, nothing that a good tinkerer can't handle. It's up to you, I only offer it as a suggestion since there are no other solutions being presented.
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

hawaiiho

Bob,

I'm a tinkerer also.  I'm afraid what I have here, though is not something mechanical.  I could be wrong, but I think  the cause

rests in that the electrial polarity is some how interferring with digital command signals.

Joe Satnik

Yampa Bob, Jim Banner and All,

If it helps,

The 2 piece (wall-wart and controller) 44212 HO/On30/N DC power pack set w/AC accesories terminals is wired as follows:

"16VAC IN" 5.5mm power jack accepts the transformer plug:

Plug inside terminal: transformer out "hot" 16VAC 120 Hz 1 Amp. 
Plug outside terminal: transformer out "common" or "return".

Transformer (alone) measures 17.1 VAC open, 15.4 VAC @ 1.1 Amp

(Which is probably within spec. for such a transformer.)


"To Track" 3-pole power out jack is  a standard 1/8" (3.5 mm) stereo audio jack.  (Don't even think about it.) 

Tip: 16VAC "hot" inside terminal--> circuit breaker (unknown Amp rating) -->tip: current protected AC accessories

Ring: 16VAC "hot" inside terminal--> circuit breaker (same) -->
  half wave rectification --> direction/voltage control --> current sensing/limiting --> ring: +/-DC  track power

Common: 16VAC IN Plug "common" outside terminal --> common:  "To Track" common (return path for both tip AC and ring DC)

Push/Insert/Release AC accessories terminals:

Nearest "To Track" out jack: 16VAC IN "hot" inside terminal--> circuit breaker (same) --> PTC (positive temp. coefficient thermister - measured 1.2 Ohms @ room temp.) --> P/I/R AC out "hot".

Nearest "16VAC IN" jack:  16VAC IN Plug "common" outside terminal -->P/I/R AC out "common".

Note: The LED pilot light circuit is directly lit by the "16VAC IN" hot and common nodes.  A diode and cap allow the LED to "decay" to off instead of immediately going dark when transformer power is removed. 

Hope this helps.

Sincerely,

Joe Satnik
If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Yampa Bob

Joe,
Two questions, is the direction switch DPDT, and how difficult would it be to switch the DC output polarity on the direction switch solder lugs?

My thought is that when the DCC turnouts were designed, R&D might not have considered the fact that the EZ Command has input for a DC controller?

When Hawaii switched track terminal connections to allow the turnout to operate, the only remaining problem is the DC controller direction switch doesn't match loco direction. It's a last resort workaround, but may solve the problem.

It is also possible that the DC locos were made before the NMRA right rail rule went into effect, and the motor wires are reversed.  RichG mentioned he had to switch motor wires on one to compensate.
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

hawaiiho

Attention:  the Bach-mann

Apparently there is a known problem with the DCC turnouts when using them with Dynamis. The throw is opposite to the selected position.  In my case the problem is that the DCC turnouts quit operating.

Is this issue is known to Bachmann and if not, they should be informed.  Also, what might we expect as a correction?

Any information would be very much appreciated.

Joe Satnik

Jim Banner,  Please contact me off-line, joebarbATwwtDOTnet Thanks.

Bob,

The direction switch in the 44212 HO DC controller is actually an SPDT.  Cut 2 foils and jumper 2 wires to change direction.

I'm not sure that everyone understands the NMRA right hand rule.

Assume an East-West chunk of straight track is in front of (north of) you and your controller is hooked up so that when the direction arrow is pointed left, an engine facing west goes west.  (Follows NMRA right hand rule.) 

If you turn that engine around on the track, it will still go west.  (Repeat the last sentence until it sinks in.) 

This allows for back to back consisting of DC engines with similar speed.

Ernie,

The TV show Addams Family ran Lionel 3-Rail-O trains.

With some manipulation, you can set the engines to always go forward. 

Set them on the track facing each other for your cornfield meet with optional dynamite.

Hope this helps.

Sincerely,

Joe Satnik

If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Yampa Bob

#23
I am confident that Hawaii understands the right rail rule, but that is not the issue. 

Once again, here is the real issue as I understand: Hawaii is feeding the DC controller output through the EZ Command controller, and when he switches the track terminal connections to make the DC controller direction indicator correct, then the DCC turnouts won't work.  If he switches the terminal connections to make the turnouts work, then the DC controller direction  switch is wrong. It is a case of "one or the other", but not both working correctly.

At this point, it seems the only solution is to ignore the position of the DC direction switch until the turnout issue is resolved/corrected by Bachmann.
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

hawaiiho

Thanks Bob.

Absolutely and totally correct.

I am seriously considering making two little stickums with arrows on them, and placing them on the DC controller where the

direction indicating arrows are located.  There-by correcting the direction arrows.

That should provide a laugh to my friends when they come over to see my brand new Bachmann layout.


Joe Satnik

Dear Hawaii,

If you want more than "live with it" on your 44212 DC controller:

The printed circuit board foil cuts (Xacto knife) and wire jumps are pretty straightforward to someone who has previously modified PC boards.

Do you know any technicians, or have a tech school nearby?

You could aviod cutting the foil by de-soldering and lifting the right and left leg of the switch.  You would still have to criss-cross wire the legs back to the opposite foils, though.

    switch
    L  M  R
    /       \
   X         X  <- Foil cuts or leg lifts.  Check with ohm-meter across the cuts to assure "open" circuits.
  /            \     

    switch
    L  M  R
    /\      \
   X  \      X
  /     \ ___\  <- jumper wire switch left leg to right foil   

    switch
    L  M  R
    /      /\
   X     /   X
  /___/      \  <- jumper wire switch right leg to left foil

Hope this helps.

Sincerely,

Joe Satnik   

If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Yampa Bob

#26
I don't have the 44212 controller, but do have the interconnecting cable that came with EZ Command.

I would be inclined to replace the output plug on the cable, switching the wires in the process.  This would preserve the controller as is for powering a DC track.

Radio Shack has the plug, easy soldering job.  The plug has a metal screw on barrel, so the wires could be switched again later if needed, or just buy another OEM stock cable.  Cables are much cheaper than controllers. 

In fact, it would be very easy to make up a separate short adapter cable, male plug on one end, female socket on the other, with the wires switched. Then all your OEM components would be preserved. 
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

Joe Satnik

Y-Bob,

The way this controller design works is to electronically choose between a "+" supply and a "-" supply, with a common "ground" in between as the return path.   

I'd be cautious about trying to reverse the plug.  The ring (+/- DC track out) returns through the common shank,
as does the tip (AC accesories, hot.)  If you swap the DC and common, The AC would then be trying to return through the +/- DC track out.  Not good.

So, you are limited to low tech "direction stickers", living with it, or 2 cuts and 2 jumps. 

I suppose you could also use the excuse "that's the direction on the other side of the oval."

Hope this helps.

Sincerely,

Joe Satnik
If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Yampa Bob

I am at a disadvantage in that I don't have a controller to study.

I have a couple of old DC locomotives that I would like to run on my DCC layout, so I will obtain the 44212 controller and study the circuitry.  I also have two extra Magnum controllers, I am curious if one of them could be modified to accept the interconnection cable. 

Thanks, Joe, for the information.
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

richG

Jim Banner posted the below on his site back in2005. Will not help right now but maybe if we ask Jim, he might continue to explore this controller.

http://www.members.shaw.ca/sask.rail/dcc/EZcommand/index.html

With Jim and Bob working on this issue, there should be some answers in the future.

Rich