# Problem with Airwire Convrtr-25 and a Tsunami TSU-2200



## [email protected] (Dec 28, 2018)

Need some help. I have a LGB Porter. We used an Airwire Convrtr-25 and a Tsunami TSU-2200 to battery power the loco. Everything was working fine. Then after a couple months after about 30 seconds of operation the sound would cut out. The sound would start working after restarting the systems but then would cut out again. The motor would run with and without the sound, then the motor stopped working. I've checked all the wiring. The speaker is 8oHms and 2 watts. I reset both the Convrtr and TSU-2200 to factory defaults. No luck. Any suggestions?


----------



## Greg Elmassian (Jan 3, 2008)

The TSU is not intended fo rlarge scale... yes, I am sure someone told you that the porter was a very light electrical load, but it has a stall current of 2 amps. That means typical running current is on the order of 1 amp or less.

Also what battery voltage do you have? (please indicate the number of cells and chemistry).

Tsunami's are famous for being very sensitive to current and/or voltage overload where they cut out. This is really the wrong decoder for G scale.

Greg


----------



## [email protected] (Dec 28, 2018)

Hey Greg. Thanks for the reply. I am aware of the limitations of using these decoders. We run them in similar setups successfully. The only difference in this case is the battery chemistry. Due to size limitations we are using a NIMH 8 cell 9.6v 2400 mAh battery instead of Lithium ION batteries we normally use.


----------



## Greg Elmassian (Jan 3, 2008)

Not sure of the minimum voltage that the decoder will run on, but 9.6 volts is pretty low. What does SoundTraxx say about that voltage?

Also, since you are using the Convrtr to drive the decoder, you have to be at least 2 MOSFET voltage drops and most likely more... I do not know the schematic of the Convrtr, but at least the transistors driving the DCC output have to be there, and that would be 0.6 volts minimum so you are running the decoder on 9 volts DCC or less... sounds sketchy.

Greg


----------



## [email protected] (Dec 28, 2018)

From Soundtraxx-

Max. Motor Stall Current: 2A
Max. Function Current: 100mA (each output)
Function Outputs: 6
Audio Amplifier: 2 Watt, 8-Ohm Load
DCC Track Voltage: 7.5V – 22V
CVP states it will work with 8.2-22v
I have no knowledge of 2 MOSFET voltage drops. But I think I understand. 

So it may a battery problem as we have run the setup with a LION battery. I do some testing.
What I don't understand is we have operated this setup in this loco for hours and had no problems until now.

Thanks for you input.

Dan


----------



## Greg Elmassian (Jan 3, 2008)

Yeah, strange, the numbers look like they should work.

Does your tsunami have the leds under the heat shrink, I have not run one in a while, seem to remember they would indicate the error condition.

The batteries should be over 9 volts until they die pretty much, so the voltage numbers seem to work.

Is there any possibility the speaker is overloading the audio amp? try a different speaker for a bit? 8 ohm.

Greg


----------



## [email protected] (Dec 28, 2018)

Greg Elmassian said:


> Yeah, strange, the numbers look like they should work.
> 
> Does your tsunami have the leds under the heat shrink, I have not run one in a while, seem to remember they would indicate the error condition.
> 
> ...


I had someone else recommend replacing the speaker; I'll do that.. I'll look into the LED. I know I saw it glowing red.

Thanks again.

Dan


----------



## Pete Thornton (Jan 2, 2008)

Greg Elmassian said:


> any possibility the speaker is overloading the audio amp


I know nothing about the tsunami rig, but I did think that myself. My old Soundtraxx Sierra used to cut out after about 10 minutes as I used it at high volume outdoors. Stop the loco and it would restart.


----------



## Greg Elmassian (Jan 3, 2008)

Page 69 or so:



https://soundtraxx.com/content/Reference/Manuals/Tsunami2/tsu2_electric_usersguide.pdf



It does have a red and a blue LED on the decoder board... when the sound stops, do the loco lights flash? that would reveal an error code

Greg


----------



## [email protected] (Dec 28, 2018)

So I did some testing. I replaced the speaker and the sound still cut out. When I turn on the system, the TSU-2200 the blue LED illuminates and remains lit and solid after the sound cuts out. The motor continues to operate. The Convrtr is sending 16v to the soundcard. The soundcard is warm but not overly warm to the touch. The sound cuts out at random times anywhere from 12-120 seconds. I'm stumped. I'm contacting Soundtraxx tomorrow.


----------



## Greg Elmassian (Jan 3, 2008)

Yeah, if the red light does not light, and the blue is showing ok, I'd come to the same conclusion as you.

Greg


----------

