Wood car fans and electrification fans:

I stumbled onto this by accident. At the link below are some photos that give a glimpse of an interesting wood car project currently underway. The car is a portable electric substation.

The car is at Western Railway Museum. Performing the work is Ten Mile Restoration and Practical Historic Preservation.

No Facebook log-in is needed to view this photo album from your computer. Though on my smart phone, I get a login prompt for some reason.
https://www.facebook.com/media/set/?set ... 670&type=1

Very interesting -- I had not known that any of these survived!

Here is a similar example (but of steel construction rather than wooden) from the LIRR:



-Philip Marshall

The Boone and SV RR uses a two car station that came from the South Shore For all of there over head wire operation. For protection the rotary converter section was covered in sheet metal , while the transformers were left out in the open.

If you want to see Sacramento Northern portable substation 1 running, come out to WRM on the last Saturday of each month, when we normally operate it. No guided tours for safety reasons, but it's a good reliable machine.

If it's like the rotary converter at Orange Empire, when it starts up, it sounds like something from Dr. Frankenstein's laboratory.

Pittsburgh Railways Co. also had a portable substation, a wood bodied car numbered 1 and created in the 1910's. While it may have served at various locations its principal use was to boost the power available during the annual Allegheny County Fair at the South Park Fairgrounds, near the PRCo interurban route at Library, PA. PRCo ran an intensive service on that line to bring crowds to the fair, taxing the normal DC supply. The car was scrapped c.1928 and the rotary converter from it transferred to earth-bound duty at PRCo.

The only other portable substation that I know of being preseved is #12 from TMER&L at IRM. Could any of the IRM people provide more detail.

Took this one in Nov. 2014

Hi,

Thanks for this unknown (to me) tidbit. What sort of output did it provide (say 600V DC)?

Doug vV

A couple more photos of the interior. I is a great pleasure to be working on this incredible piece of history.

The Sacramento Northern portable substation gets a 2300 volt, 3 phase AC input and puts out 600 volts DC. The rotary converter has a capacity of 300 KW. In the third picture there is a good view of the cast iron resistors and the three contactors. These are current limiting resistors, with three stages of resistance. When a heavy train came by, it was likely that it required more than 300 KW, so the current limiting resistors would cut in, reducing the voltage to the trolley wire forcing adjacent substations to pick up some of the load and kept this station from being knocked off line on over current. In the second photo there is a black box on the left that looks a little like a coffin. That has motor driven drum switch in it that sequences the starting of the substation. The station starts on low voltage and shuts on low current. There are pneumatic timers that prevent the station from reacting to short time variations in voltage or current.

The first picture is looking at the DC end of the machine. There is a motor driven brush lifting rig to lift the brushes off the commutator when it starts. The commutator its self is covered with arc shuts to protect it from flash overs. This was common for machines on third rail railroads, where accidental grounding of the the third rail is not uncommon. The museum has power logs from the dispatchers office where these unexpected groundings were logged. The track crews, unloading ballast from drop bottom gons, were responsible for many of them.

In the middle picture you are looking at the transformer that changes the 2300 Volt three phase to 447 volts six phase. It also has taps to allow starting the machine on half voltage to get it up to speed while being easy on the rural power line. The half voltage, full voltage contractors are in front of the transformer. Notice in most of the pictures the three holes drilled in the roof carlines. These were for the 2300 volt knob and tube wiring that came in from the machine end of the car if the power happened to be at that end. That was removed at the Museum, as there was a lack of fath in the insulation on the wires, and the wire was needed outside to help set the substation up.

It is really good that the condition of the exterior wood is finally being addressed.

Dave,

That's one fascinating piece of preserved history!

Questions: isn't the input voltage 347 6-phase for 600 DC output?

Does this machine have a amortisseur squirrel cage windings to start it as an induction motor?

How does the machine get its initial DC (stator) field excitation?

Dave, thank you for the detail description of the operation.

Similar equipment installations were installed in buildings for stationary substations. Orange Empire acquired the equipment from one of these stationary installations on the Sacramento Northern. It was installed in a building at Perris and is maintained as a stand-by power supply.

I had always been told that the transformer put out 440v 3-phase AC for the rotary converter.

Hi Jeff,

The 447 volts comes from the name plate on the transformer. I can't say that I have actually measured it myself. It has been a long time since I have looked at it. At one time I think I knew the math relationships, but no more. I set the station up and got it running in 1968. In the picture the name plate is on the right side of the transformer below the oil level sight glass. It does have induction motor windings which it uses to start, but at a reduced voltage. The field excitation DC voltage comes from a generator driven by the same motor that drives the drum switch shaft.

When we first got the station running, the machine vibrated. The local GE service man said the rotor had sat too long without rotation and the windings had sagged. He agreed to balance it if we could deliver the roter to his shop. We took the rotary converter apart with very crude tools. Lifting was done with blocking, bars, and one cable hoist. I do not know how we managed to get as much done as we did with such limited resources.

Hi Brian, thanks for your comments. Your machine is also six phase. Count the slip rings on your machine. There are six of them. The machine at OERM came from Del Paso, first sub station north of Sacramento. We salvaged that building and reerected it at WRM. It is the building that houses the BART rectifier now. Also in that building, but not set up, is another 300KW rotary, with all the supporting equipment. It was the equipment from Pleasant Grove. We got it from the University of California in Richmond. They had been using it for some kind of a metal vapor deposit operation.

It is interesting to note that the IER quit operation over the Bay Bridge just before WWII. The power supplies that powered the operation on the Bridge went to UC Berkeley and had something to do with powering the cyclotron. It was all Mercury arc equipment.