Sounds like what you’re looking for is a standard incandescent “A” shaped bulb or “PS” bulb (they have a longer neck than your usual “A” shaped bulb). Dunno if they make either of those in LED.

They do make candelabra LED bulbs with the standard base in various lumens. The enclosure for the electronics doesn’t flare. I have three hanging lights that use them. You can get them from the big box stores or any lighting supplier.

And then arc to ground and destroy the lamp socket... and possibly start the headlining on fire. The greater danger is this wouldn't happen immediately, but after some event caused one or more in the string to fail, possibly out on the line with a car full of passengers.

A story. Back eons ago, when I worked for the Chicago Transit Authority, we were re-decking an "L" platform at night, with the 600 volt platform lights on. SOP was, normally during the day when the lights were off, to unscrew the lags that held the base of the gooseneck, lift it with a pinch bar, wiggle the old boards out and the new in. In this case, when the guy drove the bar in he must have caught the wires and shorted them together because the lights in that fixture went out... but the next one in line got really bright, but only for a little while.

For an additional level of complication, consider the problems faced by museums with vintage New York City Transit subway/elevated cars - 120 volt street railway bulbs with left handed threads on the Edison base.

/s/ Larry
Lawrence G. Lovejoy, P.E.

The problem of European lamps flaring just above the screw base has been with us for some time. I first ran into it when GE moved its lamp production to Hungry. It only impacts a few of the sockets, but there is no fix for the problem when you run into it.

Years ago, Paul Class ordered bulbs for this replacement problem. Paul is still in business and may have a supply in stock for streetcars. You can ask if he can still order those type of bulbs by asking him: paulclass183#gmail.com.

Harry Nicholls
Dallas

THIS... This is very real. Look at what happened to the Memphis, TN trolley. I would say that until 2014, the Memphis Trolley was an amazing success story. Then two fires, and the line was down for YEARS, it's possible some of the vintage streetcars may never be allowed to run again. As of now, only one route is open with streetcars, probably because this route goes through a pedestrian mall normally off-limits to cars, I bet if they could of done this route with a bus, it might still not be running yet.

Like I said, in this service, the bulbs must be able to take the full 600vdc, and must be a consistent product. Find me ONE LED bulb on the market, that existed 5 years ago in it's current form. From what I can see, manufactures feel very free to change the engineering on a product at any time, and even if you buy name brand bulbs of a specific kind, there is nothing stopping them from changing the design to what the feel is a equivalent device.

Memphis saw no wisdom in line breakers and redundant means for dropping the pan, so when electrical issues cropped up, well...... no means of disconnection apart from cutting the overhead power, generally after the car was cinders.

How about this one? Otherwise, there are a few tube shaped bulbs.

https://www.greenline.dk/ledvance-parathom-dim-e27-standardpaere-18w-2700k-69104

And there seem to be quite a few "photo" bulbs available
https://www.bulbamerica.com/collections/ps-shaped-incandescent

In a 600-volt five-light series circuit, each light drops 120 volts. :)

There's several good candidates I've found while shopping around at the Bulbsamerica website.

Thanks for the link!

Brian

There have been a number of informative posts in this thread. Thanks everyone who has shared insight. I deleted a few posts related to a political rant. I'll remind everyone to save your political rants for Facebook, Twitter, etc... They will be deleted. This is not the place.

Tom Gears
Moderator

Brian - these are the two styles I use, both have the standard base:

If each bulb, device, has the same resistance, they will drop 120 volts. If the resistance varies, the voltage drop will be all over the place. If a device goes open or to a very high resistance/current draw, the voltage will go as high as 600 on that one device. Some devices that never intended to see more then 120 volts AC may do strange and scary things when hit with 600vdc, even if they are partially non-functional.

In a series circuit, all the devices will pull exactly the same current, the voltage drops on each device will fall into what it takes to make all the devices pull the same current. If you put in 5 identical devices that work nicely together, that is fine. Say that you replace one a couple years later, and the new one is more efficient, pulling less current. The voltage on that one will rise and the others will drop, until the same current flow is 'forced' onto all 5 devices.

If you have 5 in series, and the startup current/sequence varies in current, and they are not 100% in time, I bet you will get a heck of a light show, and the voltages will be all over the place.

I think something to consider is that incandescent bulbs are simple resistors that you can string in series and can know more easily what to expect in terms of voltage drop and current with a bit of basic math. LED bulbs, on the other hand, aren’t that simple - they’re little electronic voltage regulators and I’m not educated enough to say if they can reliably strung in series like incandescent bulbs without smokin’ them. Maybe someone more knowledgeable will chime in.

For the problem of running 120v bulbs from 600v, I'm assuming that you don't want to rewire to add a second wire to the socket, wire the bulbs in parallel, and feed it with a voltage regulator dropping the voltage to 120v.

What about screw-in 120 volt LEDs with a ballast resistor wired parallel to each bulb? Select resistors so that they have a lower resistance than the LEDs. This would avoid the problems with wiring LEDs in series and possible differences in resistance.

With a voltage regulator to drop the voltage to the lamp loop to say, 120v, and use 24 volt bulbs.

One possible problem with this scheme is that the resistors would give off some heat which the LEDs might not like, but the combined heat from the LED and resistor should be considerable less than what is given off by the incandescent bulbs.