PS1 smoke unit

Running about 34 volts...the video is cloudy from smoke.

I predict your smoke unit will enjoy a pretty short life running on 34 volts.

Its hooked up to a 15 ohm 25 watt resistor. Even at 25 watts resistor gets hot use frame as heat sink. 50 watt resistor is too long. 

At 40v .18v. When motor is on. Drops to 16v. Smoke motor works off chugger switch.

A series resistor is not the ideal answer.  You need power conversion with higher efficiency.  If that resistor is dropping 40 volts down to 16 at the smoke unit, it's dissipating 38.4 watts!  That's more than it's max rating, small wonder it's getting really hot.  What confuses me is that would indicate the smoke unit is drawing 1.6 amps, I know they don't draw that kind of power!

I do ...been thinkibg how to make a step up trans for motor only..20-40vs. To fit in frame.

It'll be a lot easier to drop the voltage for the smoke unit.  Crude but effective would be to simply use a host of diode pairs to drop the voltage to a level that the smoke unit will easily tolerate. 

You can find ten pieces of the 2W10M 2A bridge rectifiers on eBay, auction 17184992336 for $1.29 free shipping.  These will wire to give you twenty diode pairs that will drop the voltage about 15 volts.  If you need a bit more, buy two lots and add a few to the chain.  If you haven't done this before, you can tie the + and - on a bridge rectifier together and use the ∼ inputs to make two diode pairs, the following configuration can be created using two bridge rectifiers.  These two bridges configured this way drop about 2.8-3.0 volts under load.

Thanks..i will try.it.but what about voltage reg...Lm337 type...

The regulator is a linear regulator, so it'll require a significant heatsink, and you also will have to feed it DC.  The diode pairs I indicate will function with AC or DC and drop the voltage.  Since the power dropped is distributed along the chain of bridges, no heat sink is required.

Please note that this is just one way the Skin the Cat, there are lots of different solutions that could be applied.

It would work better fo me to up voltage to motor. So i can use 1 transformer.so at 16-18v i am putting out 36-38v. I think if i reverse diodes voltage goes up. So i can run engine on club layout.

The engine is a mth 392e...so its a 392e berkshire..

Diodes won't increase voltage!

There is no easy way to boost the voltage to the motor, that will require a step-up power supply of some sort.  What's the exact model number of that unit, I have never had to use 40 volts on the motor of anything toy train related!

Pittman motor..9237so10-r1-sp

24V .37 watts continuous.  Peak current 13...current continuous 2.4

.

I was actually asking about the exact model of the locomotive.

This is home made...

If an MTH 392E chassis, why not use the MTH motor which presumably operates at lower voltage?   I can understand if this was a one-off only to run on your high-voltage home track...but as you now mention running it on your club layout.  Just curious!

I have to go with Stan on this one.  I'd use the 12V motor that will run properly at lower voltages.  Trying to boost the voltage with a variable converter will be expensive to do for a one-off situation.

I don't have a better solution, sorry.

Pittman motor..9237so10-r1-sp

24V .37 watts continuous.  Peak current 13...current continuous 2.4

.

Tried many attemps to use a lionel motor.. Modified..kept getting hot. Large stack .extra large stack. Vertical design.

Bob hannon can tell you.. 

24V pittman cause didn't know if 12v would burn up..that engine weighs 10.5 lbs. I made the motor / wheel block. Cut the frame. So i could get 8. Mc coy wheels ..i made it like the 0ga berk.with blind wheels.

I may get a 12v and see what happens. Don't think it will have the torque.

Will have to look in to power transistor s. To up volts.

Thanks for all the in put....

My VL-BB weighs more than that, and a single 12V Pittman runs it fine.  Many large O-gauge steamers that weigh at least 10 pounds are running around with the same 12V Pittman motor, they have an excellent reputation for reliability.  The VL-BB has pulled 50 O-gauge cars and not broken a sweat.  It could have easily pulled more, just didn't have them handy.  Harry Henning's Legacy Y6B was observed pulling 90 cars using a Pittman 12V motor, again no issue.

You're selling the Pittman 12V motor short.  You just can't put 24 volts on it and expect long life!

thanks john,,,,what is the number of pittman motor,,,thanks

I can't say, it obviously has to match the size of what you have now.  You mentioned you made the mounting, so clearly it has to match whatever you have, or you'll need to make something to match.

12V motor came..it will take 20v..no problem. Now need to make another shaft extension. The mounting is same as 24v motor.

20 volts seems a bit high for the 12V motor, what's the model number?

12V motor came..it will take 20v..no problem. Now need to make another shaft extension. The mounting is same as 24v motor.

9234S004-R1

Pittman Brush Commutated DC Servo Motors

I don't see anything in the specification that says it'll take that much over-voltage.

Thats the problem..Pittman does not say max volts...where as i bought the 24v.

It will take 40vs atleast...so what i see is that they are built to take twice the stated volts. As long as you don't really over load it..

I thought the object of the exercise was to run this on a club layout with 20 volts or less?

1. You started with the 9237 24V motor (37 Watts) but ran it at 34V or even 40V.  That's fine as long as you aren't dissipating more power than allowed. 

This may unleash a firestorm but there is no such thing as a 12V motor or a 24V motor per se .  A motor's voltage is a guideline that says at that voltage it delivers some specified torque at some practical RPM with reasonable efficiency in converting electrical power (Watts) to mechanical work (HorsePower).  Not quite apples-to-apples but think how a car tries to keep its motor running at 2000 RPM (or whatever) using a variable gear automatic transmission to adjust speed.  This greatly improves MPG efficiency. I'm not aware of any model trains with variable transmission so it makes it that much more important to operate near the guideline if you're concerned about maximizing safe pulling power.

2. Now you have a 9234 12V motor (22 Watts) but you're talking about driving it at 20V?  OK, same deal.  That's fine as long as you aren't dissipating more power than allowed.   So if you're driving it at 20V to get to nominal operating speed, then you're probably not operating it near maximum efficiency.  You may say so what, but it just means that more Watts are wasted as heat as opposed to going to useful HP to pull your load.   I have no idea what it takes to power your modified 392E plus load but since you went to a lower powered 12V motor, I'd think it useful to operate it closer to its peak efficiency point which is unlikely to be 20V.

3. You might take a look at the motor MTH uses for the 392E...and compare it to the 12V Pittman you're using.  As GRJ says, there are motors out there that can pull a similar chassis and loads using O-gauge/club transformer voltages (rather than 40V or whatever).

4. This thread started with the smoke unit operating at 40V or whatever.  As GGG notes, the PS1 smoker resistors are nominally 3 Watts each.  If you're nominally operating at 20V, that's where the smoke heater resistor is 2 x 16 = 32 ohms.  Ignoring some AC-to-DC math, in round numbers 20V into 32 ohms is 20*20/32=12.5 Watts.  That is double the power of the 2 resistors so you haven't solved the initial problem of overdriving the PS1 smoke unit.

FWIW, the smoke resistors are normally over-driven from their ratings, that's how they generate the heat.  If you do the math on one of the Lionel single element smoke units with the AC regulator, you'll find it runs at between about 4 to 6 watts, and the resistor is rated at 3W.  FWIW, I've used the PS/1 smoke unit on 18VAC in a number of installations.  They do smoke like a bandit, but they've never cooked a resistor.  I actually ended up using a string of diodes in a couple of engines to lower the voltage so I could tame the smoke output a bit.

Lets remember the PS-1 smoke unit takes AC input and rectifies it to DC.  So the resistor sees DC Current and Voltage.  The other reason the resistors can take more power dissipated is that they are air cooled besides the evaporative effect of the fluid.

Stan is right about the motor rating too.  That is a voltage rating usually at peak efficiency.  Your risk is if you have a motor stall.  You then have sufficiently high enough voltage to draw too much current and damage the motor insulation/wiring.

I am not sure why you want to run at those voltages, but your above the typical 30V value that can be a deadly voltage under certain adverse conditions.  Basically your energizing a layout with voltage sufficient to kill some one especially if they grab the rails with both hands and place a load across their body through their chest.  Doesn't take much current to stop your heart from beating.  G

Thanks,   the bridge IC  did fry,   never wanted to run high  volts,  but I grabbed the rails,  nothing, not even a buss to fingers,  at 40v, ,, the reason I bought the 24v  was ,,I use a zw,  and my thought was this was max,  so if someone gave 20v it would not burn up,

Now with the 12v,  it works great,  12-14v, less bridge drop,  but it will fly at 20v, too!,  but its too fast, but also its not 20v with bridge drop..  the site solved my motor problem,  but will have to get another PS1,  that's R&D,

thanks,  Merry Christmas eve......

no smoke for Christmas...oh, well,, engine runs...

Most anything on the PS/1 PCB can be replaced, they're all generic components.

john ,, part numbers?,,

is there diagram of parts lists, 

I don't have specific part numbers, but once you know what part you want, they're generic parts.

thanks,