So here is the problem. You bought a PS2 smoke unit meant to be driven by smoke outputs on a PS2 or PS3 board. And while yes, PS2 might use roughly 6V and you can test a PS2 board smoke output by plugging in a 6V lamp, it's not the same thing.
The fact is, PV is a (the voltage that drives a PS2 headlight and smoke resistor- the board controlled transistors are PWM/Duty cycle controlled to approximate that correct average power. Again, this is a track voltage rectified source, however the return path (negative) to the control board PWMs/Duty cycles so it's NOT track power either.
@Darrell posted:I bought from MTH a PS2/3 smoke unit to upgrade my Williams GS-4. The loco has a regulated 6v power board in it that ran the original smoke unit and lights. When I hooked up the MTH unit to it the smoke was ok but nothing like what MTH smokes units can do.
Do I need to hook this up straight to track power? I will be running 18v DCC to the track, would it have to be rectified first? That should give me ~16.5vdc to the smoke unit, is it enough? NO, do not connect that unit directly to track power.
This is the unit I got:
SMOKE UNIT / PS 2 & 3 / 7.5mm POST HEIGHT / 25mm W x 36mm L / BRASS CUP 4.6mm H
Item# AA0000057
You slammed 8 ohms worth of resistance (2 16 Ohm resistors in parallel) and the DC fan, on a 6V DC output.
That equates to roughly 750mA cold for the heater which will reduce as it heats up. Then pushing 6V to the fan is on the high side of voltage, probably screaming away at top RPM.
And you may be pushing that 6V regulator near it's limit thermally and/or seeing sag on the DC.
The correct unit would be use a PS1 style for direct track power that is meant for variable track voltage.
Found on the upgrade page. https://www.mthpartsandsales.c...ts/240?type=products
