Lionel S-4 Smoke Regulator Issue

Well, there are true experts on the forum who can help more than me, and hopefully one of them will chime in, but based on what you say and looking at the parts diagram for what I think is your model:

(1) I think that the AC Regulator has fried - as they were very prone to do with what appears to be the specific smoke unit installed in your case (no longer available as a complete unit from Lionel).

(2) If your smoke unit PCB has not also fried, you might be able to track down a replacement regulator (I don’t recognize the specific product number you mention) but the resistor in the smoke unit would have to be 8 Ohm or greater value to safeguard against the regulator being overtaxed again. I think that these smoke units originally shipped with 6 Ohm resistors, and produced prodigious smoke, but Lionel soon changed the spec to 8 Ohm because of frequent AC Reg. failures.

(3) The clipped black wire is an extra ground wire that is surplus to requirements and was probably clipped in manufacturing.

(4) Really not sure you can just change the resistor or install an earlier generation “dumb” smoke unit wired direct to track power as (AFAIK) you won’t have control over smoke effects.

I could be wrong about that last point but someone else may know better.

The smoke regulator is to allow three levels of command selectable smoke volume.  As the previous post suggests, the smoke unit should have any 6 ohm resistor replaced with the 8 ohm resistor.  As for the exact part number, it really helps if you provide the exact Lionel product number.

@Hancock52 posted:

Well, there are true experts on the forum who can help more than me, and hopefully one of them will chime in, but based on what you say and looking at the parts diagram for what I think is your model:

(1) I think that the AC Regulator has fried - as they were very prone to do with what appears to be the specific smoke unit installed in your case (no longer available as a complete unit from Lionel).

(2) If your smoke unit PCB has not also fried, you might be able to track down a replacement regulator (I don’t recognize the specific product number you mention) but the resistor in the smoke unit would have to be 8 Ohm or greater value to safeguard against the regulator being overtaxed again. I think that these smoke units originally shipped with 6 Ohm resistors, and produced prodigious smoke, but Lionel soon changed the spec to 8 Ohm because of frequent AC Reg. failures.

(3) The clipped black wire is an extra ground wire that is surplus to requirements and was probably clipped in manufacturing.

(4) Really not sure you can just change the resistor or install an earlier generation “dumb” smoke unit wired direct to track power as (AFAIK) you won’t have control over smoke effects.

I could be wrong about that last point but someone else may know better.

Hancock52,

The model # is 6-28548. The last 3 digits in Lionel's part# 691ACRGES2 is assigned based on the sticker on the 8 pin IC chip. Lionel's other smoke regulators have the same prefix but different 3 digit extension at the end. I'm assuming they're for units with different resistor values and/or steam/diesel applications. Smoke unit reg 691ACRGES2 is available for $20.00. I measured the resistor and my meter showed 8 ohms which is congruent with Lionel's parts site. I guess I'll just order one...or two.

Thanks!

Dan

@gunrunnerjohn posted:

The smoke regulator is to allow three levels of command selectable smoke volume.  As the previous post suggests, the smoke unit should have any 6 ohm resistor replaced with the 8 ohm resistor.  As for the exact part number, it really helps if you provide the exact Lionel product number.

GRJ,

Model # 6-28548. The regulator is available from Lionel. The resistor is 8 ohm from the factory. I was just thinking of a way to bypass the reg but it makes sense Lionel used it to stage smoke volume hence the brown serial data wire. I'll just order a replacement.

Thanks again,

Dan

Yep, you can bypass it and tie it directly to the smoke control output of the R2LC, that also requires you change the smoke resistor to something in the 20-27 ohm range as well.

One trick to increase the longevity of the smoke regulators is to open up the heat-shrink and fold out the triac and bolt it to the frame.  You will need insulating hardware for that trick as it must be insulated from the frame, but that give it better heat dissipation and lengthens it's life.

@gunrunnerjohn posted:

Yep, you can bypass it and tie it directly to the smoke control output of the R2LC, that also requires you change the smoke resistor to something in the 20-27 ohm range as well.

One trick to increase the longevity of the smoke regulators is to open up the heat-shrink and fold out the triac and bolt it to the frame.  You will need insulating hardware for that trick as it must be insulated from the frame, but that give it better heat dissipation and lengthens it's life.

GRJ,

I settled on ordering a replacement. I want to keep the variable smoke intensity feature. I'm already planning on bolting it to a metal heatsink bracket or frame. I already have the insulating silicone mats and hardware. Hopefully it'll stay together a bit longer this time!

Thanks,

Dan

@gunrunnerjohn posted:

The smoke regulator is to allow three levels of command selectable smoke volume.  As the previous post suggests, the smoke unit should have any 6 ohm resistor replaced with the 8 ohm resistor.  As for the exact part number, it really helps if you provide the exact Lionel product number.

I just replaced the 6 ohm resistor with a 8 ohm on my early Legacy FEF.  While I loved the smoke output, in the long run I'd rather have a happy regulator.  It's doing alright with a 8 ohm.

Hi

I am on my 3rd regulator board with 8 ohm resistor

The smoke unit runs for 10 minutes then the resistor fries the batting and the ohms reduce to 2 ohms and the regulator burns out, on inspection the resistor is totally black . The smoke output is far too exsesive and I wonder if the smoke volume is stuck on full all the time overheating the smoke unit.

Any advice would be most welcome

That doesn't make much sense.  The only thing I can think of is a possible wiring issue.  If you have an 8 ohm resistor and no wiring errors, the smoke regulators generally don't instantly go up in smoke.

One thing to consider.  If you're bolting the regulator triac to the chassis, you MUST have insulating hardware, the metallic part on the back of the triac of the smoke regulator can NOT be connected to anything, especially chassis ground!

What's the exact product number for this locomotive?

Thanks

It doesn't go up in smoke straight away it runs for about 10 minutes, then the resistor gets very black and the ohms reduce  to about 2 ohms. During this time there is an enormous amount of smoke

It's a lionmaster challenger 6-38090

I wonder if somehow it's stuck on smoke boost setting ( key 9) permanently

I'm at a loss, if the boost setting was stuck, you'd have lots of other issues running.  I think I'd swap the R2LC, that's where the serial data commands for the smoke regulator come from.

Thanks

Will try that, fingers crossed