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

Bob,

Your already one up on me. I ran out of ideas several days ago.


grumpy

Everyone may think I am crazy but I am wondering that due to design that is the way it is supposed to work. It may be that the DC contoller when plugged into EZ command controller trys to consider the turnout as a DC loco. A shot in the dark.
Don ???

hawaiiho

Don,

If that's the case the HO Tech support people at Bachmann don't know anything about it.

They were in the dark and said they would research it, talk to others in the department, and then get back to me by

email if they figured it out.


Yampa Bob

#48
We should probably make up a special trophy for "stumping the panel".  :D

Don, your idea has some merit, there is some kind of conflict between the turnouts and the DC controller. Another case of either/or but not both.

I'll be at Caboose Hobbies next week, see what I can find out. I found a picture of the decoder, appears to have two wires in and three wires out.  Interesting.
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

Jim's EZ-Command power supply diagram on his club's website shows that the DC controller's AC power is ignored if the EZ-Command's transformer is plugged in.  Correct?  (Stereo plug tip-AC, shank-common return)

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

Joe Satnik

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


Yampa Bob

#51
Joe
Your are correct. However you cannot have the EZ Command transformer plugged into the "16 V AC IN" jack on the EZ Command controller, AND the DC controller transformer (through the DC controller) plugged into the "From DC Controller" jack on the EZ Command controller, AT THE SAME TIME. Both jacks share a common ground, the result will be either an AC voltage connected to a DC voltage, or two AC voltages that are not supplied by a common source.

I do not know yet if the DC controller plug shank is at AC ground potential or DC ground potential.  But you can't have two separate power supplies sharing a common ground without proper phase or blocking circuitry.  It's a case of either one, but not both. 

Simply unplugging the EZ Command transformer from the wall is not adequate, as the plug tip still disables the DC input tip, thus removing the tip potential from the entire circuit.  The instructions in the manual should say:  "When using the 44212 DC controller, remove the EZ command transformer plug from EZ command, unplug the transformer from the wall, roll it up and put it in a drawer.  It is not needed, and must not be connected to the EZ Command controller."

Call it "thinking out loud" if you will, I have tossed this around in my mind for several days.  It's impossible to diagnose without the components at hand to test. It's like a Doctor doing a physical over the phone or by email, with no documented history of previous similar illnesses.

Hopefully I will have more information next week.

Regards
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.

pdlethbridge

 The 2 wires in and 3 out sounds right for a decoder in a switch. The 3 out would be like the blue yellow and white on a regular decoder for directional lighting with the blue as common. the other 2 of the 3 wires would be straight or curved.    Does the decoder get programmed like a regular decoder and get its own address?

Yampa Bob

I compare it to the usual 2 wires from a power pack AC accessories connected to a selector switch (the decoder) and the 3 wires out connected to a dual solenoid, with one wire as common feed.

I have briefly reviewed the programming instructions, but frankly haven't tried to comprehend it as I have no plans for using DCC turnouts.  Personally I think this is carrying automation too far.  I'll take old reliable manual throws or selector switches any day.

I don't like commenting on things I don't have personal experience with, this is all just theorizing. If I'm wrong, my wife will still fix me breakfast tomorrow so no big deal.   8)
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.


pdlethbridge

my thought was that the switch, decoder equipped, receives a signal via the track like a loco. On my layout, my turnouts are decoder equipped, a digitraxx ds 64 that controls up to 8 turnouts each receives a signal from the track, that lets me control them from my hand held power cab.

Jim Banner

Quote from: Yampa Bob on February 04, 2009, 10:16:49 PM
... you cannot have the EZ Command transformer plugged into the "16 V AC IN" jack on the EZ Command controller, AND the DC controller transformer (through the DC controller) plugged into the "From DC Controller" jack on the EZ Command controller, AT THE SAME TIME. Both jacks share a common ground, the result will be either an AC voltage connected to a DC voltage, or two AC voltages that are not supplied by a common source.

Actually Bob, you can.  When you plug the E-Z Command transformer into the E-Z Command, it automatically disconnects the ac power (but not the dc signal) being received from the 44212.  It does not matter that there is a common connection between the jacks because there is no common connection between the transformers.  The transformers used to power our model railroads perform two, equally important functions.  They reduce the voltage to a safe level.  And they isolate that voltage from the power line.  That way there is no chance of full line voltage ever appearing on our rails.

Incidentally, that is the reason that manufacturers are banned from using simpler, cheaper auto-transformers in model railroad power supplies.  Auto-transformers do have a common connection to the power line and plugging one in one way and another in the other way could result in up to 240 volts at up to 20 amps appearing between their low voltage outputs.  Even if your outlets meet your National Electrical Code!

Simply unplugging the E-Z Command transformer from the wall does create a problem.  Leaving the low voltage end plugged into your E-Z Command stops it from receiving power from your 44212, even if the latter is plugged in and turned on.

If your E-Z command transformer has a higher rating than your 44212 transformer, you might want to use both of them so that the former gives you maximum power to your E-Z Command and the latter allows your 44212 to function.

Bottom line, the designers got it right.
Growing older is mandatory but growing up is optional.

Yampa Bob

Possibly, but consider this, if it's ok to use both transformers, wouldn't the instruction manual so indicate?  Both the picture and note indicate using only the DC controller transformer.  Or is the manual wrong?

Personally, I wouldn't take a chance using both transformers at the same time as it contradicts the manual, which might void the warranties.  Perhaps the designers should re-study this issue and add clarity or emphasis in the manual.

The designers may have "got it right", but the fact remains that the controller seems to be in conflict with the turnouts.

Meanwhile, I have searched the net for days and found no mention of the symptoms in this thread. Let's hope this is a one time fluke, and not an epidemic. 
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.