MTH NON POWERED UNITS

when i run a dummy in a 20-25 car consist, it almost always requires 2  powered units...if you cant live with 3 units, the best bet is sell the dummys to buy powered locos.....plenty of us always looking for non-powered,now that mth doesnt sell them in premier....imo, its not too cost effective to try to power a dummy unit.....

Jim that's was my thought also. Some of these units cost me $250 plus do you think asking $200 is a fair price. they are all in excellent condition and I believe I have the boxes.

Assuming that these dummies are specific road names that you like, maybe buy from the secondary market, powered units of the same construction but, of no particular road name, then swap the shells and sell the dummies. Of course, if you can find these same units powered in the same road name, then just sell the dummies.

i feel asking $200 is  a good place to start...

Run shorter trains. Make sure the non-powered unit and the cars you are pulling are properly lubricated to reduce drag on the powered unit..

The added weight and friction (the wheel bearings and the flanges) of a dummy locomotive amount to very little when compared to the weight and resistance of a 15 - 20 car train. The physics say otherwise. Compare the weight of your entire train and the weight of the single dummy loco - the train weighs more and there are more wheels to roll (more resistance) than on your dummy. This should indicate that your dummy may have a problem - does it roll freely? Do the trucks swing easily and properly? I have pulled more than one train (with modern equipment) of some length with a dummy in the mix with no issues. Maybe it's your powered unit.

MTH diesels are fairly capable of pulling 50-60 cars. I certainly dont think a dummy is a 30 car handicap. So either your layout has huge grades, you're running trains of nothing but die cast cars, you need oil somewhere, or you need to verify that you have the full 18 volts on the track. Low voltage and a heavy load makes the motor driver work overtime, and that seems to make more heat than anything else. 

I assume that the 18 volts is measured when there is no engines on the track 

No, you need measure it with the trains running. 

I have a thought how about the length of time you run a 50 to 60 car Train? If I were to run it for a couple of minutes as compared to maybe 15 minutes would that make a difference?

I usually run my 15 to 20 car train about 12 to 15 minutes and it starts out running  fine but then after about 8 to 10 minutes that is when I notice the powered unit begins to heat up and runs erratically. If if remove the dummy unit and run with just the powered unit it runs cooler and has no issues.

I don't think the unpowered units create that much drag.

Also some reference track voltages below.

In the middle of this video is a 5 eng MU (3 powered 2 unpowered) pulling 41 cars. These are premiere 2 rail using DCS and a z1000 brick. There are over 5k scale miles on the unit and run very well. I used to check on temperature way back when by feeling the top of the shells but find it unnecessary now. If anything traction from a standing stop is an issue(wheels will spin on the rails and make odd noises plus i haven't cleaned my track for over a year) so i back bunch to take up coupler slack on the first 10 or so cars then throttle forward at scale 1 to 2 mph and off we go.

My 5 eng 3 rail MU which runs concurrent with above is all power,no back bunching needed here. My track voltage reads 17.9 to 18.3 vac using a harbor freight dvm with the 2 MU's rolling(scale 25mph) and 5 other engines on but either sitting or side track switching duties.

voltage trains running 25 smph.

Remember that the power required to keep the train moving goes up with the square of the speed. So run your freight trains slowly and your locomotive will generate less heat.

I run single power units  2 motors with a dummy and 20 cars sometimes more at shows. Run them for hours never a a problem.  

I think the real key factor here is; exactly which brand of "dummies" are being used. I do know that Atlas O "dummies" have all the gear drives in place within the trucks, just no motors in the unit, thus they provide lots of additional drag. Conversely, I have an A-B-B-A set of MTH Southern Pacific F3 units, with only the two A Units being power units, and they have handled more than 60 cars, with no issues at all (at a train show, with more than an hour of running).

I have another question, when I power up my z4000 to 18 volts to the track which is connected to the TIU and no engines on the track I am getting a 1amp current draw. Is that normal. Is that what the TIU draws?

OG3RAIL posted:

I have another question, when I power up my z4000 to 18 volts to the track which is connected to the TIU and no engines on the track I am getting a 1amp current draw. Is that normal. Is that what the TIU draws?

Good question. I use a z500 to power my TIU but never measured current draw.

OG3RAIL posted:

I have another question, when I power up my z4000 to 18 volts to the track which is connected to the TIU and no engines on the track I am getting a 1amp current draw. Is that normal. Is that what the TIU draws?

Are you sure that your Z4000 is showing "1 amp", and not 0.1 amp?

Have you checked your dummies wheels to see if they are in gauge?  If they are too narow, that would produce drag.

I think you should wash your hands of them and sell them to me, for cheap!

Seriously, I drag two or three dummies and don't notice any problems.