# QSI in Bachmann 2-8-0 with MRC controller



## East Broad Top (Dec 29, 2007)

Here's my theory on wiring; DCC install experts, tell me where I'm overlooking something...

1) Tap the power for the QSI board from the track inputs, allowing the track power to continue to the stock Bachmann board to power the smoke unit (via the switch) and the firebox lights. 


2) Remove the LS/NMRA polarity switch, hooking the motor directly to the QSI board.


3) Run headlights, chuff switch, etc. off QSI board as illustrated in the instructions.


Now, to test this theory, I hooked everything up as such, without hooking up the chuff, speaker, or lights. Essentially, I'm just trying to run the motor. Using the MRC controller in what I'm assuming is factory default settings, my speed control is spotty at best. The motor spits and sputters at low speeds, finally picking up and smoothing out at around half throttle.


That doesn't seem right to me. 


One would think "plug-and-play" would be a bit easier than this, so I'm certain I'm overlooking something somewhere.


Thoughts?


Later,


K


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## StanleyAmes (Jan 3, 2008)

Kevin 

The 2-8-0 is not a plug and play locomotive, wish it were. 

Many electronic control drivers do not like the capasitor/inductor circuit used in this and many other locomotives. Unfortunately this circuit often has to be removed. In the case of the 2-8-0 the circuit is just above the motor and can only be reached by removing the boiler. 

Also you need to make sure that you are connecting the motor leads directly to the QSI board and not through any other board in th e locomotive. 

I have a bunch of 2-8-0s and over time I standardized the install by moving the motor leads to a take the place of two of the wires going to the tended. That way I can access the tender more easily to try out different installs. This is a good place for the QSI decoder as well as the speaker is normally placed in the tender. 

The downside of this is that such an install requires a function decoder be placed in the locomotive to control the lighting in the locomotive. AN alternative is to place the sound/motor device in the boiler and then use 2 of the unused wires to the tender for the speaker connection. 

Hope this helps a little 

Stan


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## East Broad Top (Dec 29, 2007)

I tried removing the capacitor filter on the motor, since I know it plays havoc with RCS's stuff. Performance was no different with it on or off. If it does no harm to remove it as part of the install, then I will most certainly do so. One less bit of electronics to clog up the works. Yes, the motor is connected directly to the QSI board. I'm wondering if there's some kind of system disconnect between QSI and MRC controller, but I was under the impression that both systems used the NMRA's DCC standard. 

My thought was to put everything inside the boiler, and use the former chuff contact wires for the speaker connection. Since there seems to be no reason to access the board itself as a regular matter of course, I figure hiding it in the boiler makes sense. 

Later, 

K


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## Road Foreman (Jan 2, 2008)

Kevin, 

What is the MRC controller?? Need more info.. 

BulletBob


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## East Broad Top (Dec 29, 2007)

It's MRC's "Prodigy" DCC system. 

Later, 

K


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## Road Foreman (Jan 2, 2008)

Kevin, 

If it is the "Prodigy Express" it may not have enough power to run the loco.. The "Prodigy Express" only has 1.6 amps @ 14.5 volts.. You may need to get there 8 amp booster.. 

BulletBob


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## Greg Elmassian (Jan 3, 2008)

There has been some strange behavior exhibited with high current motors and the QSI, call me sometime Kevin, there is a new firmware release that allows some help. It's not generally available, I have been testing it this week on Aristo and the prototype USAT plug and play board. 

Regards, Greg


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## East Broad Top (Dec 29, 2007)

It's the Prodigy Advance 2. I've used it to test other DCC throttles in a K-27, so I know it's got the guts to make things work, and works quite nicely to boot. Just not in this case, which has me a bit befuddled. Darned electrons going through the rails. What's up with that???  

Later, 

K


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## Peter Osborne (Jan 5, 2008)

Are you running the loco on rollers? I had an issue where I was getting intermitent shorts because the spacing of the axels did not allow every wheel to be supported. When I ran it on a 3 feet section of track, no problem. The Prodigy Advance has enough juice to run the Connie. That was my test bed for a Loksound XL install in the Connie. 

Peter.


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## East Broad Top (Dec 29, 2007)

It was on rollers. I'll have to look into that. Logic tells me that since the problem went away at higher speeds, there's something else going on, but I'll definitely try again on my usual test track. 

Later, 

K


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## Greg Elmassian (Jan 3, 2008)

Kevin, the issue I was referring to was surging at low speeds, went away at higher ones. Also sometimes going to speed zero did not always stop. 

Regards, Greg


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## East Broad Top (Dec 29, 2007)

Greg, that is precicely what is happening with what I've got here. Glad it's not just me. I'll give you a jingle later this week when I have time to work on it. 

Later, 

K


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## Greg Elmassian (Jan 3, 2008)

Sounds good Kevin, if you have the programmer, you need to download a new version that will allow you to manipulate a parameter that was not available before. I have it if you need it. 

Regards, Greg


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