Answering NH0401's question, on the current NEC compliant PHW single cabinet ATC/ACSES as applied to diesel electric locomotives in passenger service, the 74 volt feed from the locomotive is dropped internally to 32 volts within the system. The incoming feed to ATC, ACSES and the event recorder is wired around the battery knife switch, pulling the switch does not shut them off.

PC

Good, many steam locomotive generators are already 32 volts Direct Current.

Dirty direct current - microprocessors demand a very clean variety of DC.

dave

It's not particularly challenging to develop a box which takes dirty intermittent power on one side and outputs smooth as a baby's bottom DC on the other.

Per Mr. Cooks reply, it appears that the PHW system has a self contained power supply that supplies clean 32VDC to the equipment. Sounds like the 32VDC spec. dates back to the days of steam.

Ross-thanks for your description of the equipment applied to the 614. Wonder where you hid the batteries ?

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Yeah, they used such a box on US&S 4 & 9 aspect cab signals for years...

As to pictures of the 614 installation I'm sure there are many out there. The next picture I take will be my first, so others will need to help in that area.

The full set of batteries was installed in a newly created battery box on the firemans side of the main tender.

I neglected to include that full HEP was also installed so that 614 can pass through HEP should she be running behind a unit ahead of her which is supplying hotel power to the train. Also, she was equipped with a diesel control stand in case we were forced to take a dismal with us (Lord forbid!!!)

Ross Rowland

Everyone please keep in mind that if these systems eventually become mandatory, the purchase cost and the cost of installation are only the "beginning". After that, you have got to have a qualified tech verify the correct operation of the system at required intervals, and since the system is safety critical, if you are running in territory where it is mandatory and it does not work, you do not get to operate until it does work. It adds a few more items to the list of things that require maintenance and troubleshooting, and can potentially put you out of service.

PC

I probably did jump the gun a little on this topic but, I just wanted to see if anyone was thinking ahead.

The first generation of PTC is an overlay of currention operating practices. Signals and track warrants will still be the main means of train seperation while PTC keeps engineers in check. This will probably allow steam locomotives to continue to operate under their normal super scrutiny. But....

The next generation of PTC will most likely use GPS as the main means of train seperation. Signals and track warrants will only be back up for PTC. Computers will tell engineers how fast to run at all times to optimize train meets and keep following trains from slowing too much or stopping at a signal waiting for the train ahead to move along. When this system comes into effect practically everything on the railroad will have to have PTC.

As a result of Metrolink and other accidents, you can be pretty sure that the system will be anticipatory like the current Amtrak ACSES equipment. The faster you are going, the further in advance the system will take action on its own to initiate brake applications and drop power. This will not be a cheap system, at least not in its first few years, the price of the equipment might come down a little after that. And I suspect that you are correct, all the locomotives operating on designated lines will eventually be required to have the system. Sometime in the not too distant future there might be no exemption for steam or any other heritage equipment.

One potentially good thing about GPS based systems is the potential to cut down on "ghost" penalties, interference caused actuations, and unexpected aspect flips. A lot of the current equipment is EMI sensitive despite the use of shielded cables, and you quickly find out how useful a scope meter, plastic cable spacers, and tie wraps all are.

PC