AC-12 / Tsunami HELP PLEASE

[SteamDonkey74]

I had noticed that their plug was numbered incorrectly, too, but I didn't bring it up as I thought you had wired it properly.

Well, I am glad to know that you got it solved. I spent too much time on helping my kids with some things last night and didn't get back to you with any additional info. I am glad you got it, and here's hoping the magic smoke hasn't left your decoder.

[Carl Sowell]

Well I corrected the wiring and the sound works well. Decoder will not program, loco will not run and both lights stay on all the time. I'm told by Soundtraxx that the decoder has tripped a motor fuse and will have to go in for repair. Brand new decoder ( not inexpensive ) and has to go back for repair. I bought the thing 1 to 1-1/2 years ago and can't find original billing invoice so if I send it in it will cost me more. I am totally tired of all this decoder and especially the sound decoder crap. Can't even read cv's, need more goodies ( $ $ $). Anybody want a GS-4 with sound?

[SteamDonkey74]

How are you trying to program it?

I find that, with my Zephyr, that I can program it in OPS mode when using my DT-402 throttle (I use an isolated portion of "mainline" track and disconnect everything else) and that I can program it with my Sprog II, but I can't very easily do the regular program track paged-mode method that Digitrax prefers in their documentation.

I wonder if it may have gotten damaged slightly with the accidental reverse wiring. It seems. To have pins 5 and 8 swapped would swapped the gray and red wires. That doesn't sound good, but maybe it's not a big deal.

[Carl Sowell]

SD74,

I'm not trying to program it. There is power to the decoder now but the program commands in page mode are not taking. It's mute point now as the decoder is in the mail to Soundtraxx. The man I spoke to today at Soundtraxx told me they have had several tsunami's for the AC-12 come back with motor fuze tripped. That very thing happened to my attempt to put tsunami in my GS-4. The GS-4 had the factory shorting problem fixed before I put in the decoder. He told me that those two locomotives have had "problems". Soundtraxx has not even seen an IM AC-12 to check out installation of their decoder. Lot's of communication amongst manufacturers.

[SteamDonkey74]

Now I am worried.

My decoder installation has been fine so far, but I haven't had a motor fuse trip. Did they indicate what causes this to happen.

[woodone]

Someone needs to explain just how the jumper plug is numbered wrong.
Once I find pin number 1 that is all I need to wire up the decoder to a socket.
Carl , would you tell us how the jumper plug was miss numbered.
Might save someone the same heart ache that you had.

[woodone]

Originally Posted by SteamDonkey74

Now I am worried.

My decoder installation has been fine so far, but I haven't had a motor fuse trip. Did they indicate what causes this to happen.

Most of the time it is a motor to frame short that takes out the fuse.
Once Carl tells us just how the jumper was wrong, I might be able to tell you what happened.

[Carl Sowell]

OK gang, here goes.

First Soundtraxx tells me that the motor fuze tripping is common among the GS-4 and so far the AC-12.

IN the AC-12, that I received, the plug in the tender has a dummy plug on the board. When you take out the dummy you are supposed to be able to plug in a decoder with 8 pin plug on its harness. Sounds easy and it is if you are smart enough to catch the fact that the dummy plug pins are identified incorrectly.

The pin is labeled as follows:

Pin #1 - Pin#4 are on the left side of plug and are numbered from top to bottom

Pin #5 - pin #8 are on right side of plug and are numbered from TOP to bottom


The problem is the right side because it should be numbered #5 - #8 from BOTOM up.

I have never worked with decoders with pins and did not recognize the mis-labeling done on the dummy plug. I had a sheet that showed pin assignments by color and that is what I used. Unfortunately the right side was wrong.

Hope that helps. BTW, by reversing the right side wiring probably caused the fuze trip in my opinion. Oh well, I'll learn to be more cautious in the future.

[dstuard]

By having the right side of the plug numbered in reverse, and wiring the plug based on the numbers on the jumper board (not an illogical thing to do), the connections on pin 8 (right rail, red) and pin 5 (left motor, gray) are swapped. This puts one side of the motor to the rails and one to the decoder output. Not good. Similarly for the connections on pin 6 (front light, white) and 7 (light common, blue). The upshot is that the motor wont run (and the fuse would blow) and, if an LED, the light wouldn't light.

The connections were set uo so that if a decoder were plugged in backwards, no damage would result. Not so if half the decoder were in backwards.

A properly wired plug will work fine Although misnumbered, the jumper board is wired correctly. Just don't pay attention to the numbering.

See http://www.loystoys.com/info/nmra-pl...d-sockets.html

[SteamDonkey74]

I suspected a misnumbering of the dummy plug when I was doing my conversion so I did two things. The first is that I looked up several different sources to confirm the correct numbering (and Loy's Toys, Litchfield Station's docs, and several others all were in agreement). The second is that I popped the tender lid off my 0-8-0 to see how that one was wired to its harness just to make extra special sure.