Just when you think you've solved every problem

[Restorer32]

Looking for headlight bulbs (2 contact bayonet base) for a 1918 Rauch and Lang Electric. Oh, I forgot to mention these are 90 volt. Dome lights are 80 volt.  Need those also.

Edited July 23, 2019 by Restorer32 (see edit history)

[stvaughn]

I’m not familiar with the battery setup on your R&L but is there a way to just tap off 6 or 12 volts to operate the lights?

[Restorer32]

Thought about that but have not actually stared at the wiring diagram enough. I do know the batteries are wired in series so I am not sure how you would tap into just 1 battery output.

[TerryB]

5 minutes ago, stvaughn said:

I’m not familiar with the battery setup on your R&L but is there a way to just tap off 6 or 12 volts to operate the lights?

Yes, my thoughts too but the wiring harness will have to be modified to do this.  It does highlight those little head scratching moments when originality versus practicality present themselves.

[Restorer32]

It sure does. Online I have found 90 volt LED bulbs but still trying to figure out if the bases are the same.

[TerryB]

In your battery setup that is batteries in series, the battery that is connected to ground could be your 12v source. The side that is not grounded would provide the output to run the headlights.  You would have to make a custom connection with a wire to that point.  I’m assuming you have individual 12v batteries in series in your setup.

[tripwire]

Any chance a 115v bulb work?

Try these guys: http://www.surplussales.com/bulbs-incan-panel/Bulbs-4.html

Here's an example of something they have.

 

Wes in VT

[Bloo]

75 volt railroad bulbs maybe? https://www.zoro.com/ge-lighting-mini-incand-bulb-15s113dc-15w-s11-75v-15s113dc-75v/i/G2357135/

[Restorer32]

7 deep draw 12 volt batteries in series. Hoping not to have to modify the wiring harness. I have found 120 volt bulbs online that would appear to work. Just need to verify the bases and wattage.  The bulbs in the sidelights are visible so have to consider that also.

[Bloo]

120v is going to be REALLY dim on 90 volts if they are incandescent.

[edinmass]

How about a 6 volt motorcycle Gell battery and run regular six volt bulbs. Just have to run the wire..............and charge the battery for show times.

[mike6024]

Home built electric vehicles have that same problem. they carry a 12 volt battery for accessories, separate from what they call the "traction pack" which drives the car. The 12 volt accessory battery can be charged off the traction pack by a transformer of some sort. The traction pack might be 300 volts.

 

I will try to look it up, on Northbay EV website.

 

I think using 12 volts for the lights would be easier.

[Restorer32]

Not that simple. The owner lives in France and hopes to use the car as regular transportation at his beach house in Normandy. We replaced all the plate glass on this rolling greenhouse with laminated safety at great expense and he wants everything to work as original if possible. We did purchase an 84 volt charger and have to find a converter so he can use it on European current. I find it interesting that this car, a 1918, was still in use at least until 1937 according to the NJ registration decal on the windshield.

[mike6024]

DC/DC Converters

 

DC/DC Converter    Elcon 
Brusa DCDC died after 1.5 years; Inside 
doesn't look roadworthy mechanically. 
Replaced with Elcon which lasted 1.5 years; 
bias shunt resistors overheated, probably 
because they were potted. Bought another 
Elcon that looks different on the outside.

 

DC/DC Converters
Last Updated: 10/03/09

EVs need 12 volt DC power to operate standard automotive accessories, such as lights, horn, radio, fans, and such. There are several ways to provide this 12v power.

You can use a 12v battery and the original alternator, belt driven off the electric motor. It works the same as it does in a normal car, i.e. it's not particularly elegant or efficient.

Some budget EVs eliminate the alternator, and just use a large deep-cycle 12v battery that gets recharged when the traction battery is recharged. It works, but makes for weak headlights and poor accessory performance unless the 12v wiring is improved to eliminate the typical 1-2 volt drops between battery and loads.

Another less-than-satisfactory approach is to tap the traction batteries to get 12v. This tends to unbalance the batteries, and creates safety problems unless the traction pack is itself a low voltage (24-48 volts).

Most modern EVs thus use a DC to DC converter. This is an electronic power supply that takes high voltage DC power from the car's traction battery pack, and provides an isolated 12 volt output to power standard accessories. They are small, light, silent, and have no moving parts. The DC to DC converter is usually set to provide a solid 14 volt output so lights and accessories work the same as they would in a normal car with the alternator charging the battery. The most common DC/DC converters used in conversions are made by Todd, Sevcon, Curtis, and Vicor.

Special thanks to Lee Hart for the assist on this page.

Suitable DC/DC converters for electric conversions are available from most EV parts suppliers. Follow this link for a current list.

[TerryB]

DC to DC converter crossed my mind buy I only have used low power ones in electronic circuits and I didn’t know what’s available to operate the load requirements for head and tail lights.  If you can use LED bulbs the current requirements would be much lower and allow the use of a smaller DC to DC converter.

[lump]

About 60 years ago, my dad found an old Mazda light bulb cabinet full of really old bulbs. I still have LOTS of those bulbs, and some of them are huge, round, with visible tips from when the glass was blown. I have often wondered what the really odd-shaped ones. and what voltage they might be. Any suggestions? Maybe I have what Restorer32 is looking for? 

[Bhigdog]

Throw enough money at it and you can do anything. How badly does he want original?.........bob

[Restorer32]

Badly enough that we also restored an original mercury arc rectifier and charger to use as a static display alongside the car.

[Restorer32]

And not a question of "throwing money". Nothing wrong with wanting things correct. Unless we take this car to Hershey it will likely never be shown. Owner does not care about trophies.

[lump]

Restorer32, do you have any idea what those special bulbs would look like? I'm just wondering if any of those old "oddball" lightbulbs might be what you would looking for. 

[Restorer32]

We do not have the original headlight bulbs. The sidelights and courtesy lights just use common 2 post bayonet base bulbs .59" in diameter. Only remarkable thing about them is they are 90 and 80 volts.

[mike6024]

http://www.1000bulbs.com/category/led-ar11-lamps/

http://www.1000bulbs.com/category/led-r12-elevator-lamps/

 

Halogen Bulb 120volts (AC)

 

http://www.lampsplus.com/products/75-watt-clear-double-contact-halogen-light-bulb__47d79.html

 

 

Edited July 24, 2019 by mike6024 (see edit history)

[Spinneyhill]

What is the base? You say 2-contact bayonet. What size and are the pins opposite or offset? e.g. BA15 or BAY15, or some other size?

[Restorer32]

.59" diameter base, 2 contact, opposite pins. There look to be some choices online we can try. The sidelight bulbs are visible so appearance is a factor with them

 

[Restorer32]

We have to be very careful. 84 volts DC is a heart stopper. I have a pacemaker/defibrillator in my chest so I stay away from the wiring. This car sure is fun to work on.

[chistech]

If you are able to find some original bulbs but not step down the voltage to common headlight bulbs, the owner will always encounter the issue of trying to find a bulb if one blows. I imagine the light switch is fed with a single direct feed. Step the voltage down to twelve volts between that feed and the headlight switch  and it will automatically allow use of 12v bulbs anywhere else on the car. If the horns are fed off the light switch, another small terminal board can be installed with that high voltage feed going to it first, then any high voltage accessory can be fed off the terminal board including the step down for the lighting circuit. All this can be kept under the dash and the original harness kept in place, all that’s being done is a small accessory harness is being added to the system. Just an idea. Something like this.

 

https://www.powerstream.com/dc-72.htm

 

Note: realize the input voltage is greater than the unit above but they make others and are probably a good company to talk to about solutions to your issue.

Edited July 25, 2019 by chistech (see edit history)

[Frank DuVal]

This isn't rocket surgery,  

 

What terminal of what battery is connected to ground?

 

Then tap the other terminal of that battery for your 12 volt source. You will have 12 volts from that wire to ground. The polarity of that 12 volt source is determined by which terminal of that battery is connected to ground, but incandescent bulbs DO NOT CARE!

 

Simple....

 

Now, as far as disconnecting the existing lamp wiring from the 84 volt source, that needs to be done or things will go downhill.😲

[mike6024]

It is not proper to tap off that way. You have a bank of 7 batteries in series. They will discharge uniformly. Remain "balanced." And they will charge uniformly.

 

If you just tap off one of that set in series for accessories, then it discharges more than the others; the bank becomes unbalanced.