Weaver SAW board to ERR conversion question

Yes, you can use that cherry switch.  One wire from the cherry switch to the locomotive frame, the other wire from the switch to the "chuff in" terminal on the Cruise Commander.  Use the 3-wire connector that ERR supplies to connect the Cruise Commander to the Railsounds Commander board.  Connect speaker wires to the Railsounds Commander.  You won't connect anything to the chuff sensor inputs on the Railsounds Commander board, the sound board will get the chuff input via the 3-wire connector.

THANK YOU BOB!!!   Do you know if that would be a single wire from the engine through the tether?  I have a single light blue wire, but one diagram says it's a headlight connection.  The only other wires are a connector that had a purple and black wire for the smoke unit.  Seeing the diagram calling out the headlight has me stumped as it doesn't list anything as a chuff switch.    This is just some diagram I received a while back and I didn't know if it is supposed to represent all SAW boards or not.  Thanks again!

Hi Nick,

I'm not familiar with this particular locomotive or with SAW board connections.  Perhaps someone else will chime in or you could call Weaver and ask which wire in the tether carries the chuff signal.  It's a fairly recent loco so their service department should know.

Just ring out the harness end to end to see where the chuff switch is connected in the harness.

I have the SAW documentation if that would help you, I'll attach it to this post.  I'd make sure you have a common from the switch to the Cruise Commander, don't count on common to the frame and through the wheels.

If you'd like synchronized smoke, you can check the ERR announcement and order the puffer, or you can build one from the attached schematic.

Thank you John, this really helps!  It does connect to the front lamp terminal per the document sent.  That is what was stumping me.  However, it does say another wire should be connected to pin 6 of U6, but I don't have anything connected on mine.  I will dig more tonight. 

I have one more question.  I have 2 wires for the smoke terminals on the SAW board, but the ERR instructions say to only use one.  Per the SAW document, one is a smoke unit hot lead and the other is a chuff output so I'm not sure which one to use and then where does the other go.  I did try the chuff output lead on the ERR board and it would immediately trip a circuit when I fired it up.  The engine wiring is a mess on this engine with the red flashing light and the firebox glow so I'm trying to avoid pulling it all off if I don't need to.

I wired a couple other engines that went much smother, but they were models with the Hall effect sensors and Seuthe smoke units so there wasn't much to them. 

Thanks again for the help gents. 

The smoke output goes to the smoke unit for the ERR installation.  The chuff output has no parallel for ERR, it's not used.  The module I posted is designed to modulate the fan from the microswitch as well as feed the chuff input of the ERR board so you can have synchronized smoke if desired.  The ERR also specifies not to connect the smoke unit common to the common terminals as I recall, but rather connect it to frame ground.

I'm not sure what the Chuff Output is on the ERR Cruise Commander, no such output exists.

I'm not sure sure what wiring you're trying to preserve, sometimes that's more trouble that it's worth.  If you connect something to the Cruise Commander and it trips the transformer, that's really bad.

Thanks John.  The chuff output I mentioned was from the SAW board and is listed on the manual you linked.  I see my issue now as I had that lead connected to the ERR board when it should have been the hot lead.  That linked really made it clear.  I don't run smoke anyway so I'm not too concerned.  Hopefully I can wrap it up tonight and test it out.  Thanks again.

Nick

Good deal, you even had me confused.

Well, I finally have it.  It was the smoke unit chuff output from the SAW board that was the trigger input on the ERR board.  Thank you all for your help!

Everything working now?

I'm just tinkering with the chuff cam more to get the 4 chuffs evenly spaced.   All else is good.  Thanks again for the guidance.