Large Scale Central

Aristocraft PCC

I guess I just need a reassurance here, If I run the PCC on an overhead wire, can I run the Roundhouse Sammie on the same track? The Sammie not having insulated wheels.

As long as the PCC overhead pick up is completely isolated from the wheels the answer will be yes.

I wouldn’t trust any isolating switch wiring in Aristo locos.

Well, one of the rails will have to be connected to power, so you need to ensure that not both wheels of the PCC are not connected to the motor/main board.

I’d wire the pcc for both wheels tied together, left and right… greg

Greg Elmassian said:

Well, one of the rails will have to be connected to power, so you need to ensure that not both wheels of the PCC are not connected to the motor/main board.

I’d wire the pcc for both wheels tied together, left and right… greg

Sorry to be picky Greg.

That is a double negative. It should be either:

…ensure that not both wheels of the PCC are connected to the motor/main board.

OR

…ensure that both wheels of the PCC are not connected to the motor/main board.

yeah pretty crappy English… was not happy with what i said will go back and clarify what i was trying to say…

Greg

One of the issues the Pittsburgh Railways had when the P&CS was running steam locomotives on the line at night, was the overhead wire would become contaminated with soot and oil residue. This could cause some running issues with the streetcars running on the line by day.

Just a thought.

But yes, if the rails/overhead and streetcar are wired up properly, then you can run a live steamer and a streetcar (powered by the overhead) on the same track.

On the bottom of the PCC car there’s a switch for Track power or Overhead power, so Greg, if I understand correctly, if I run on an overhead power wire, switched to “O” on the trolley, I still need to power 1 side of the track to complete the circuit.

Yeah, I don’t remember the wiring, but you would hope that it would be set to take power from either rail, but that also would short the rails together.

Time for the old voltmeter…

You might read up on George’s mods to the PCC, and he references my PCC pages too.

Greg

Thanks Greg, I’ll check out your site.

I have not located the user manual for the PCC, it should detail track power requirements when using the overhead.

Perhaps someone has a link to it.

Greg

Mike Wlez said:

I guess I just need a reassurance here, If I run the PCC on an overhead wire, can I run the Roundhouse Sammie on the same track? The Sammie not having insulated wheels.

Here are electrical conditions which will work:

Overhead is live; one rail is return path, other rail is dead, rails are insulated from each other.

Overhead is live; both rails together are return path, rails are bonded to each other.

Electrical condition which will not work:

Overhead is live; one rail is return path, rails are insulated from each other, AND it remains that 2-rail power can be used.

In this case the overhead substitutes/duplicates for one rail - this is often what on-board switches do in traction models, change current path inside model from one rail to pantograph/pole while keeping current pickup on other rail. In that case the overhead & one rail are the same/connected.

Ehh, clicked quote instead of edit and thereby created duplicate post - you would think that with quote and edit buttons being in diagonally opposite corners of the field …

But then I guess it could be claimed that having a broken foot and being on pills for muscle spasms in back kinda stacks the odds …

I’m not sure in which direction they are stacked, but, yeah, they are stacked …

Greg Elmassian said:

I have not located the user manual for the PCC, it should detail track power requirements when using the overhead.

Perhaps someone has a link to it.

Greg

Actually, I’ll dig out the box this weekend, it may still be in there

Found the owners manual that was included in the box for the PCC. It’s very vague. It has a section on the Power Switches which mentions “Sliding the switch to the front of the car, the “O” position will turn the trolley pole on and set up the car for overhead catenary power operations.” That’s it, nothing that mentions power has to go to one or both of the track rails.

Typically in such arrangements one motor connection is changed from one of the rails to the trolley pole/pantograph while other motor lead remains connected to rail/wheel pickup on one side.

Guess in this case the question is which side, the left or right?

Find that out with clip leads, one to pole, one to one rail, then try other rail.

After determining which rail needs to be live, the other rail can be disconnected from electrical supply and thereby rendered dead.

At that point Sammie can run okay.

As long as you don’t use reverse loops, but just use point-to-point straight, or a continuous run circle/oval

Or you could power both rails with the same polarity and not worry about what rail needs to be powered.

David Maynard said:

Or you could power both rails with the same polarity and not worry about what rail needs to be powered.

He’s getting better!

David Maynard said:

Or you could power both rails with the same polarity and not worry about what rail needs to be powered.

you mean like this?

  • January 31, 2018 10:39 AM CST Share

  • Overhead is live; one rail is return path, other rail is dead, rails are insulated from each other.

    Overhead is live; both rails together are return path, rails are bonded to each other.

The original question was can I run my Sammie with non insulated wheels and the PCC using the rails and overhead.

YES

easiest way is what several people have stated. power both rails same, shorted together, overhead is other power lead.

I think we got a bit off track, trying to solve the issue if you could run regular track powered locos and the overhead too.

And there are some ways to do that too.

Greg

It would still be smart to find out for certain which side of the current the switch for overhead operation is connected to.

–> And, importantly, I recall having read of a case of a traction model where that switch did not disconnect one side of the wheels but rather added the pole or pantograph to the wheel pickup wiring on that side.

Don’t recall what scale or what model and it was several years ago.

Without having detailed documentation these things need to be tested.

And even with documentation they need to be tested for factory wiring errors.