ps2 conversion shuts down, etc

 Thanks G, will check.

 It sounds great. Good smoke output too.

Although this board is in a converted engine, it shouldn't matter. All the guts are from a MTH G gauge dash 8?

 G, How much power does the smoke unit's fan alone draw?

Is the fan on the other supply or the same as the smoke unit?

Joe, the issue is if the smoke motor is defective.  When working properly, the motor only draws 50-60ma.

Thanks John.

I'm just wondering if the smoke unit's fan was attached to the elements supply, could that shut down the board if it was shorting or drawing too much?

The MTH smoke fan motors are twice the size of the O motors so the current draw will be higher.  The fan is powered by the 5V regulator that powers all the micro chips and ultimately the power supply to the main processors.  So if it draws high current, even if just momentarily it can cause the 5V regulator to shutdown. 

Got that the guts are the same, but what sound file was loaded?  G

Twice the size of what motor?  The smoke fan motor is the smallest motor in the locomotive!

I narrowed a problem down to a dead short in one truck across the wheels and pickups. I noticed that if the bottom removable plastic cover is tightened to much, there's a dead short inside. Sounds easy to find, but I haven't gone farther. I left the cover screws snug and all was well?? It ran good when I ran it.

Why not find & fix the short before you wipe out a PS2 board or two?

I'm just wondering if the smoke unit's fan was attached to the elements supply, could that shut down the board if it was shorting or drawing too much?

Unplug the smoke unit wiring harness from the PS2 boards and then try it out...see if that eliminates any problem. 

Should have been more clear.  G gauge smoke units are bigger.  They have 3 16 ohm elements in parallel and the smoke fan motor is much larger than the O gauge smoke fan motor.  G

Oh, that makes sense!  I wondered what you were talking about.

 Ok, let's see.

John it's G scale with G scale MTH guts.

CRH, because it never came up again for months and I got lazy with other projects across my bench.

G, It has a GP30 or GP35 soundset inside right now if I remember?That was in during the shut down.

 I put the original G gauge Dash 8 file back in when I got it and the speed remained fast. So I reloaded the GP soundset for more accurate sounds.

I guess I would look at tach reader gap and flywheel condition.  Are you sure the MTH trucks are from the same sound set.

The other thing to do is make a new tach tape with one or two more stripes to slow it down.  G

 The condition of the MTH flywheel I would say is perfect. I was concerned about grease as the flywheel is down in there with the gear box. I cleaned it and it did not make any difference.

 I had considered a new tape with a correction in the number of stripes. I didn't think it would survive if the grease got to it. I figured I would just keep this engine as a lone switcher until it acted up.

 I'm in the process now of converting another engine. When it's done and I'm sure there's no problems, I'll install this board for a test run. It should be nice weather by then and I can run it harder out back! I like the idea of trying it without the smoke unit connected as a further test. I have trouble narrowing down electrical problems that are intermittent like this one.

But that's only if the conversion is using a MTH G Gauge smoke unit. A Lot of conversions that I've done use smaller USA Trains smoke units which are comparable to a O gauge type. Only room for 2 heaters in those. The big MTH One-Gauge Big Boy smoke units have room enough for 3 or more heaters.

Shutting down and slamming to a stop ain't good. Some MTH PS2 boards will do that for no reason...Seems Barry B. once commented on this problem a year or so ago. I had a One-Gauge Hudson that would do that for no reason. Could almost set your watch by how often that thing would shutdown...and it would stop at dang near the same spot on the layout every time. I had about 50 other loco's that wouldn't do that...only that Hudson..those boards got swapped out and went into some O Gauge engine.

Chuck,

.those boards got swapped out and went into some O Gauge engine.

Which is likely to do something similar down the road, if it encounters the same track/power situation as did its bigger cousin!  

I've seen this on two different occasions with two different engines, and have heard about two others.

 After an hour or so of cleaning I can finally see my work bench! Six things going on at once. I'd rather be finishing these:

instead I'm getting two feet of snow all at once. and it was 51 degrees yesterday??

Early on he stated all MTH guts, including trucks transplanted.  G

Sounds like the main rectifier shutting down.  I repaired one where the board did not have any special changes for 1 gauge.  MTH does make a special board with the rectifier wired in so it can be heat sinked to the chassis, and a larger flyback diode that also can be heat sinked.  G