# simple explanation of wiring a qsi titian quantum in a sd70 usa train



## tomthetank (Sep 3, 2013)

simple explanation of wiring a qsi titian quantum in a sd70 usa train . Have someone walking me through it needs some stuff before i start project was wondering if there is a how to step by step video or something , new to this and have qsi book but not to happy about soldering all new . Thanks Tom


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## Greg Elmassian (Jan 3, 2008)

You can do it without soldering if you don't need constant brightness on the lights. Done right, it will take more time to open and close the loco than to wire it. 

http://elmassian.com/dcc/dcc-installations-overview 

Greg


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## tomthetank (Sep 3, 2013)

Thanks for the help Greg, Tom


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## Greg Elmassian (Jan 3, 2008)

What you make up is a couple of cables that plug into the existing wiring, and attach to the motor and track terminals. 

I'll try to find some pictures, but you can unplug the standard wiring and plug these in to make the "conversion".... you can later unplug the QSI and go right back to stock wiring in seconds. 

Regards, Greg


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## tomthetank (Sep 3, 2013)

Greg, after some asking and researching, i disconnected the wires from the sd70 card that came with it, i labeled them. So from what i understand i have to connect the front right power and splice together rear right power and same with left side.then use resistor for front and back light. Now question is there are 4 wires in back for power2 red and 2 black . Question is when i splice the 2 black rear right wires together with other front right black wire ( also with the red wires) , do i connect a lead from all those wires _
And run 1wire to qsi (1 red lead and 1 black lead from the 2 red and 2 black wires? Thanks Tom


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## Greg Elmassian (Jan 3, 2008)

Now read this page: 

http://elmassian.com/trains/motive-...t-motive-power/usat-quick-a-dirty-dcc-install 

Greg


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## tomthetank (Sep 3, 2013)

Thank you for that Jeff, Tom


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## Greg Elmassian (Jan 3, 2008)

Jeff who?


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## tomthetank (Sep 3, 2013)

Greg, thanks for simplifying this step by step for us beginners. Would you know how to or where to find which wires for the usa trains sd-70 from the headlight, fs lamp 4 wires 1 red 3 black. rear lamp 2 wires 1 red 1 black ,and the listed as L 2 on front ( next to nose headlight socket ( nothing plugged into it) which goes into the usa board as L 3 it has 5 wires 4 black and 1 red. for the qsi titian quantum . Thanks in advance, Tom


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## tomthetank (Sep 3, 2013)

sorry Greg. dont know where jeff came from my apologies


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## Greg Elmassian (Jan 3, 2008)

No problem... 

If you do the quick and dirty, then you don't have to change the lighting. 

Changing the lighting is a BIG task, the common grounds are all wrong, weird voltages, and incandescent bulbs which require regulated voltages... also the bipolar LED is very tricky... 

Greg


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## tomthetank (Sep 3, 2013)

Greg, Tom I have a question regarding the qsi quantum titian, I dont know if your familiar with it ? It 's a question after the i followed the steps to your link I have tried and separated the the right and left wheels right and rear right side and same for left , my question is do i run i wire from one lead from the left and right side? the qsi shows right track into 2 separated terminals and left track into 2 separate terminals which means 4 wire. I can email you diagram, thanks Tom


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## Greg Elmassian (Jan 3, 2008)

Tom, I was an original beta tester of the QSI Titan, and am very familiar with it. 

Pins 1 and 2 are connected together, likewise pins 12 and 11... the reason is because more current flows and the socket uses 2 pins connected together to handle more current. 

Remember that the colors will be mixed since the trucks are wired identically, but since one truck is physically reversed, you will have a red and a black to pins 1&2 and likewise for 11 & 12. 

Be SURE to use a meter to ensure all left wheels are on one track input and all right wheels are on the other. 

Greg


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## tomthetank (Sep 3, 2013)

thanks i did that so i guess its with the nce programming i have the ph 10 r and have that wired up i'm trying a few things hooked up at a time . So far i have the motors and power hooked up and cooling fan , Only thing that works is the cooling fan i have to find stuff on you tube to program engine, Read nce book and no luck and getting confused more and more by you tube vids but they seem less confusing, Thats how you learn.


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## tomthetank (Sep 3, 2013)

Greg one other thing , the front and rear motors, i have in J1 # 3and #10, in layout it shows plus and minus plus to #10 minus to# 3 on the wires is it red and red or red and black and 1 lead wire for each of the 2 wires? sorry thanks again tom


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## Greg Elmassian (Jan 3, 2008)

red and black mixed.... remember the trucks are reversed, track pickups and motors. 

get the track pickups right first, then put on rollers and make sure the trucks run the same way... the trucks wired wrong will make a nasty short. 

Greg


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## tomthetank (Sep 3, 2013)

ok thanks tested wheels still correct as far as the sides go. now upto At this time you have connected the track pickups to the decoder, both front and rear truck. 



Now we are going to feed the decoder output to the entire loco. 



Take another JST and plug it into EITHER of the 2 remaining "loose" connectors, and connect the 2 wires from that connector into the MOTOR + and the MOTOR - leads, these are the orange and gray wires. You have a 50% chance of getting it right, just hook up the wires.


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## Greg Elmassian (Jan 3, 2008)

Right, decoder output, which normally goes only to the motor, now goes into the board where the track pickups connected. You only will use one connector from the decoder to the main board. 

Greg


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## tomthetank (Sep 3, 2013)

[No message]


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## tomthetank (Sep 3, 2013)

can i email u qsi wire plan so im on same page as you? sorry


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## Greg Elmassian (Jan 3, 2008)

What wiring plan, these connections, or something else? 

you have the track pickups going into 1&2 and 12&11 ....... the output of the decoder on 3 and 10 goes "into" the existing mother board. 

Is there something else? It's that simple.. 

Greg


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## tomthetank (Sep 3, 2013)

http://elmassian.com/images/stories/motivepower/USAT/nw2/nw2_truck_wiring.jpg 
so connect black front with red rear and do again then when connect run 1 lead or both wires to j1 3 and 10 or connect with j1 1 or 2 and j1 11 and 12


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## tomthetank (Sep 3, 2013)

greg as stupid as this sounds i took the original board out that came with unit wish i found you when i got the engine coulda sent to you and paid you just cant grasp this, Thanks for the help


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## tomthetank (Sep 3, 2013)

greg as stupid as this sounds i took the original board out that came with unit wish i found you when i got the engine coulda sent to you and paid you just cant grasp this, Thanks for the help


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## tomthetank (Sep 3, 2013)

ok thanks got it post crossed thanks for the patients


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## Greg Elmassian (Jan 3, 2008)

OK, so the original board is completely gone? One option is to put it back, and do the "quick and dirty"... if the wiring is messed up, then we can proceed to the traditional "hard wire" installation.

Allright, let's make this educational for all then, we can post it here. How about you email me pictures and I'll post them and we can go step by step. Virtually all the USAT locos are wired similarly, so it can help a bunch of people. 

email me a picture of what the chassis looks looks like so I can see the current state of the wiring. 

Greg


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## tomthetank (Sep 3, 2013)

Greg, thanks for the help I have a 7:30 pm to 4 am shift so i do apologize for the confusing questions . Trying to get too many things done at once, Turns out i had the wires reversed as far as the 2 front and rear motors. I had a friend go over with me and also applied what you showed on your website and in your replies. Being new i thought it 'd be follow diagram and thats it. After getting away from decoder for a day or 2 and looking at it again, It made more sense i did email you a qsi diagram, if that s what you want to post. Again thanks for your patients Tom


PS as far as sound on qsi i have to find the cv #'s but spoke to someone and thats starting to make sense also. Friend has been helping me with trouble shooting 101 and what you have explained is all making sense now. Tom


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