That would be great. I'd also love to know how to determine the voltage/current requirements of a DC motor.
If a railroad signal application, (in question), back then they were likely still using some glass jar/wet cells. I can't recall the voltages per jar or how many they'd series up to make things go.
Glass jar wet cells generated about 1.5 volts per cell. Output voltage was determined by how many cells were connected in series. Telephone companies also used wet cells for backup power with 16 cells connected in series for 24 volts total output.
My friend got back to me. It's called a Brush Flasher and it was used in signs. " Brush flashers are generally used for spelling out signs one letter at a time, or work of a similar nature." Hawkins Electrical Guide 3 1917
At least we know what it is now. So we're talking about a piece of machinery which would in some way need at least 110-120vac power to operate?
Not necessarily. Edison's passion for DC power was still wide-spread in the northeast well into the 1920's. This was especially true with slow-to-change companies like railroads. In fact, Columbia University still had 120 Volts DC in two of its dorms as late as 1955. This was a surprise to many incoming freshmen who had not bothered to read the Student Handbook, also fatal to many razors, radios, and record players.
Anyone want to hear a story about 100 volts DC? 110 VDC actually. In my railroad experience as an electrician I often had to work on some of the railroads passenger cars. Normally the cars I dealt with are 32 volt DC cars. The cars usually had a gen/motor with a spicer drive/ clutch on an axle to charge the batteries. We often had troubles with the battery charging and make frequent adjustments. I was never very careful in the car electrical cabinets as the voltage really didn't hurt if I touched something live . Manually pushing in charging contactors was not dangerous unless there was a large current draw then the biggest danger was from flash burns. At one point my railroad bought the Algoma Central. Now the company had a fairly large fleet of cars to use for charters and special events. Again these were older cars with spicer driven gen/motors and batteries so I applied my tried and true trouble shooting techniques and was quite surprised that instead of 32 battery volts there was in fact 110 battery volts. I felt like I got beat up !! One thing I never forgot after that is that Canadian cars were for the most part ALL 110 VDC. I assume the trains were longer and voltage drop was an issue. There are American cars that had 110 volt electrical systems but I never encountered them. Not to hijack the thread but 100 volts direct current REALLY HURTS !! Randy
Yes. I'd forgotten that DC was more popular decades ago. Such as the Milwaukee Road's choice of a 3000vdc electrification system. *Sigh* Guess that'll get me booted as a fan of their company.
Wow. This is a REALLY interesting piece of history. Now how do I go about generating 100VDC to power it up?
Seems in pretty good shape. Another interesting element is the question on what the output would be to each terminal. Would it be the same is the input voltage?
If you try to power it up, I'd do it outdoors. If it fizzles, if anything like old train transformers, it is a fire hazard and will stink like crazy.