LGB Uintah: Massoth #8415001 Pulsed Smoke Unit Installation - Neat!

LGB333

LGB333

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In case folks haven't seen a pulsed smoke unit working in a DCC equipped locomotive, thought I'd share this information. I just finished installing a DCC Massoth eMotion XLS Sound Decoder and a Massoth #8415001 Pulsed Smoke Round Boiler-style Unit into an LGB Uintah that I'm working on for a customer. Some sections of the Massoth German to English translations in the Installation Manuals are not that clear so I was very frustrated getting the smoke unit to work properly. I thought I had a defective smoke unit until I contacted my Massoth dealer in Germany who gave me clear directions, and now it works like a champ! I had to build from scratch a platform to fasten the smoke unit to based upon the large cavity inside the Uintah's smoke box, and then covered it with metal duct tape to protect the glue joints from smoke fluid........see photo. I'll also try to attach a video of the Uintah and smoker operating on my roller wheels test stand.......not sure this forum's system allows videos to be posted or not. But you can view the video on my Website.
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The solution was to connect the Brown wire to the decoder's A3 "pulsed" connection, and the Black wire to the decoder's DEC - ground, not the assumed DEC + connection. The A1 - A5 outputs are normally (-) so Ground would normally be (+). Who would have guessed it!

Tom
 
so the black wire wanted ground, which was DEC-

no one should identify the decoder common (usually blue) as a ground... it is the common and yes indeed it is positive voltage.

(this is because decoder function outputs are really inputs, they are an open collector transistor that connects to ground when enabled, so the "other end", i.e. the common must be positive)

Greg
 
Greg Elmassian said:
so the black wire wanted ground, which was DEC-

no one should identify the decoder common (usually blue) as a ground... it is the common and yes indeed it is positive voltage.

(this is because decoder function outputs are really inputs, they are an open collector transistor that connects to ground when enabled, so the "other end", i.e. the common must be positive)

Greg
Click to expand...

Greg - See the photo of the Massoth XLS Sound Decoder: The Massoth Instructions for the Pulsed Smoke Unit stated to connect the supplied two colored cable leads, Brown wire to the XLS decoder's A3 (- ) connection (CV114), and the Black wire to the "Ground - it would have been helpful to state whether it should be Ground + or Ground -. You also change the XLS decoder's A3 CV114 to "30" to activate the "pulse" feature from the connection. The Smoke Unit's other two Black wires are connected to the Track Power. Note that all the A1 - A4 connections on the XLS decoder are (-). So, since the Smoke Unit's Instructions didn't specify whether the Ground should be positive (DEC+) or negative (DEC-) connected, then logic told me to connect the smoker to the positive (DEC+) Ground......doesn't that make sense since, as you can see on the XLS decoder photo, the A1 - A4 connections are all 22 volts negative (-). When I did that, the smoker would work for a about 20 seconds then stop. But I was advised to connect it to the negative Ground (DEC-) and then it worked great. So, could you further explain why my assumption about using the DEC+ Ground was incorrect?Massoth XLS Sound Decoder.png
 
The point I tried to make is there is NO +ground, but common, which is positive... but NOT ground.

  • The manual you show indicates GND as - as ground.
  • It indicates +22v as common... DEC+ (that plus sign means positive voltage)

nowhere does it say the common/DEC+ is ground... common is just that, common tie point for function wiring. It should never be called ground, ever. You will confuse yourself (again).

Likewise it sort of also reinforces what I said about the function connections, they actually switch to - (ground)... again that is why the common is positive +


(The only place you will find someone calling ground a positive voltage is very old British cars, the body was connected to the positive terminal of the battery... )

Hope this clears it up... (common means something different than ground)

Greg
 
To be fair (although 'lazy' terminology) is is 'not unusual' (I won't use the word 'common' ;) ) to use the term 'ground' to refer to the 'commoned' connection for ancillary devices.

You can, of course, have a '0v' ground connection, with negative and positive supply rails relative to this 'ground potential'.

It all depends where you deem your reference point to be.. Also, it is only at 'ground potential', if it is actually 'grounded' (connected to your local ground), Otherwise it is floating with respect to local ground, and could be anything. :nerd::nerd:
 
Moved
 
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i think I will leave this thread to those of you that understand this gobbledygook.
 
Greg Elmassian said:
The point I tried to make is there is NO +ground, but common, which is positive... but NOT ground.

  • The manual you show indicates GND as - as ground.
  • It indicates +22v as common... DEC+ (that plus sign means positive voltage)

nowhere does it say the common/DEC+ is ground... common is just that, common tie point for function wiring. It should never be called ground, ever. You will confuse yourself (again).

Likewise it sort of also reinforces what I said about the function connections, they actually switch to - (ground)... again that is why the common is positive +


(The only place you will find someone calling ground a positive voltage is very old British cars, the body was connected to the positive terminal of the battery... )

Hope this clears it up... (common means something different than ground)

Greg
Click to expand...

Greg - Okay, I get it, the term Ground means use the DEC (-) terminal on the sound decoder. So, my terminology was incorrect about the DEC (+) terminal which is +22 volts. The Massoth Pulsed Smoke Unit's Installation Instructions stated to connect the black wire from the Brown/Black two wire cable to the Ground terminal on the Massoth Sound decoder. The Brown wire is then connected to the A3 (-) terminal and when its CV114 is changed to 30, it creates the pulsed output. So, contrary to my original criticism, the Smoke Unit's Instructions does not need to state connect the Black wire to "Ground DEC (-) terminal", since Ground explicitly means the DEC (-) terminal on the decoder. What confused me was the A3 terminal is (-) and connecting the other wire to DEC (-) seemed like a connection conflict (-) to (-) but it wasn't. As they say, "my bad"!
 
Short translation of John's post for the mildly curious, but not wanting to become an electrical engineer:

The smoke units need pulses of voltage from 0 volts to a positive voltage
The decoder does pulses, but switches it's output from sort of undefined to ground, i.e. it pulses to ground not pulses to positive voltage

The circuit with the transistor basically "inverts" the pulses so now you are applying pulses of positive voltage to the smoke unit.

This same thing happened on the Bachmann K27 locos, where the pulse from the "chuff switch" was inverted from what most sound units needed.

Greg
 
Sorry to bump an old thread however I am in the process of converting the same loco with the same equipment and having a similar problem. Rather I have set up a maganetic clock, which works fine with either the smoke generator or the sound card but not through the smoke generator to the sound card into the suggested external "clock" plug In terms of what I have tried it is as below.

- Reseting both the sound card and the smoke generator
- Resoldering the wires from the smoke generator to the Massoth board again

The equipment being used is
Massoth xls 8210088
Massoth 8415001
Mxion universal Clock 0018
Mxion xd pro
My main question is the solution that Massoth suggested is that for the loco not having a clock and the pulses being set up through the sound card rather than a clock?
-
Thanks in advance
 
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