Stupid question

Hello, i have a kinda stupid question here. What does make that wining noise when the train departures? I don't know how to explain it, but i'm talking about the sound that goes way high when the train starts moving, and it sound like it's changing gears when it's accelerating. Like in this video: http://www.youtube.com/watch?v=SLDsikaUFEU

Also, is there any site that has info about the bart trains itself?

Each train car has a transmission, just like the gears in your car, but bigger. That's what is making the sound.

I thought the trains were using electric engines that don't need transmission...

these are the "new" rehabbed cars. To get a bit technical here:

the 3rd rail is still 1KV; the new cars' motors are AC drive. 3 Phase.

What you are hearing is the electronics controlling the voltage and frequency (phase) going to the motors. It is an interesting sound-- sounds like shifting gears as the motor picks up speed. These cars have one motor per axle, 4 motors. Two on the X end and 2 on the Y end. There are two propulsion inverters, one for the X, and one for the Y.

To develop the 3 phase signal, IGBT's are used (integrated gate-bipolar transistors), essentially some big momma transistors that can handle the voltage and current. Early on in the development, a few of themshorted out, the result was akin to an explosion.

Going back a few steps from the IGBT's, they are controlled by fiber optic cables, and back another step, software control.

So, when the signal to accelerate is generated (in the front car), the signal is sent "trainline" to every car, and, zoom... up to 3mph/sec/sec. When a 10 car train (or 9, or 8) is standing room only during commute, these trains really suck the juice!

Does a train operator have to know all of this? I'm impressed!

no, this is ET (electronic tech) stuff. TVET-- transit vehicle electronics tech

We don't have to know it, but a lot of us do.

Hi there, I see that you are a Operator for BART. I used to be an Operator for Sacramrnto Regional Transit Light Rail. I was woundering hot to get on at BART. Please email me as I am bad with these blog sites. paperracelegal@hotmail.com. Thanks ---Aaron

TreoBART's picture

Thanks for the info, that's really cool!

A.T.'s picture

Cool. I like to hear the sound of the newer cars. it may sound retarded but they actually relax me. The A-Cars are cool because the T/O cabin has more room, but the C-Car beats the A-Car doors closed. The cabin may be smaller, but the car is universal. (Can be a lead or mid-car) I also like to sit in the lead car and watch the control console.

If you go to http://bart.gov/index.asp and click on "about bart" and then click "history & facts" you will learn everything you ever needed to know about BART and then some.

ekliptikz's picture

No disregard all of that, the real reason is magic. The conductors are wizards.

I would have started a new thread but I could not figure out how to do it. It never asked for me to enter a password and then requested the password that I originally entered and when I tried for a new password, it said that user name had already been issued. Whatever.

What I would have like to have posted was this. Living in Napa, to me, the weak link in the whole Bart system is not having a huge parking structure fight off Hwy 80 out by Pinole somewhere. If I could park my car for $10 a day in such a huge structure, I could jump on Bart and go to downtown SF. But I have to go to Richmond which is not right by the freeway and try to find a spot and expect my car to be broken into, or fight my way down to Berkeley and not get a spot. So it is far easier to just drive to downtown Sf and park. Why spend millions on trains, track and operators when the footprint for a huge multilevel parking structure is already there. Or better yet have it right by the freeway especially designed for those of us up notrth. I'll bet people from Ukiah, etc would jump on Bart were this available. Kind of like having a city bus with a tine little door that only lets tiny people in. I would have one out by Martinez for the people who come in from Sacramento.

Del Norte instead of Richmond.

The El Cerrito Del Norte station is THE commuter station.

Easy on and off from east or west 80.

Parking lots and parking structure.

A bunch of bus lines, local and those from farther out such as Vallejo and WESTCAT to Martinez.

There are also at least two Park & Rides, one in Hercules and one off of the Richmond Parkway. They are serviced by WESTCAT bus service that goes directly to Del Norte via I-80.

The Richmond BART station sucks.
jbap21

I would not park in Richmond, for that matter I avoid anything in Richmond.. The majority of people that live there don't take care of it..