Asking for a friend. Friend of mine wants to install a 480V 3-phase HEP generator for his tourist train. He is wanting to do up roughly 7-8 cars (1 lounge and 6-7 coaches). All coaches would have heat and the lounge car would have AC/heat and some cooking capabilities. He’s also wanting to do a whisper watt style generator as it is much quieter. What size kilowatt or amperage generator would any of you all that have experience only would recommend? Thank you for your replies in advance.

Backwards - first, choose the HVAC systems, kitchen appliances, and all other electrical loads the generator will be expected to power, than add up the power draws for all of them combined. Take that figure and add 25% to it, and you can start shopping for the generator based on that number. If you need to round to the nearest available size, round up not down. Otherwise, you'll end up trying to match the load total to the existing inexpensive generator, leaving you with a couple minisplits and a toaster oven. The excess capacity is to keep the generator working more comfortably, deal with the strings of Holiday lights that you will use on special occasions, and starting loads for the compressors and resistance cooking heaters.

If starting from scratch, I’d suggest hiring a pro to figure all that out. You need to add up all your running and starting wattage, apply some factors & overhead capacity and then convert it to kVa. You’ll also need to size transformers for each car. Oversizing wastes money, undersizing wastes equipment.

I think others can tell you their particular experiences, but they likely won’t specifically apply to your situation.

My two cents…

Let me carefully add from stories I have heard and read from people who deal in Diesel power that you should probably avoid Cat for your prime mover. Apparently they are a company that tries to keep repair and replacement parts availability totally to themselves and is making owning and maintaining their engines more inconvenient and expensive.

Whatever you do, don't put yourself in an Apollo 13 situation where you have to find the minimum components to have operating so you don't overload the generator to the point of failure.

Thank you all for your replies. I will definitely consult a pro.

What I have heard from being an off and on truck driver is that Caterpillar would sell their engines at close to cost and then make up for it in parts, while also not allowing aftermarket suppliers to license their parts. So, you get a good deal when it is new but later on you are paying three times as much for a starter etc. I worked for a guy twenty years ago who, due to a bad previous experience that he ranted about constantly, wouldn't consider Ford semi-trucks second-hand, because they mainly used Caterpillar engines. My understanding is that GE did the same thing with their locomotives.

Don't overlook McDonalds and their ice cream machine supplier Taylor.

A word to the wise about HEP. Many transit agencies and Amtrak, incorporated a circuit to start the HVAC systems after a slight delay, once the HEP comes up. Each car a randomly set time delay to assure that the entire train didn't slam a heavy load on the HEP system before it up and stabilized. At MARC, we used 5 second intervals over, I believe 30 seconds, to bring each system up in a way that didn't bog down the HEP. I don't remember exactly what the individual system load was for the bi-level cars, in the winter, but it was a substantial one, and staggering the cars coming on line, was a good idea. You can imagine what the load would have been on a long distance Amtrak train in day, which had sat all night of HEP.

I believe Amtrak figured that one F40PH could provide HEP to 18 cars, since only one unit in the consist provided HEP (if all was working well it would be the trailing unit on a multiple unit lash up, which was done so the engine crew wouldn't be constantly subjected to the run 8 scream of the prime mover generating HEP). On a one unit consist they just put up with it. I've had a couple of cab rides on single F-40 unit Amtrak trains generating HEP. It was loud, and this was in the days when the horns were directly over the cab and hearing protection was considered to be for wimps. Probably contributed to the fact that my ears now ring pretty much constantly in my old age (that and good ol' Rock and Roll).