First-Hand:The Lights Go Off All Over the Camp

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The Lights Go Off All Over the Camp

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Submitted by Ralph H. Baer

It's WWII and I am in Normandy on Military Intelligence duty, living in a Chateau which earlier that year had been the Luftwaffe's headquarters....not too shabby. Most of the rest of the guys lived in temporary housing built by Army Engineers (of whom I had been one before I got transferred to M.I. duty).

Somewhere along the line the camp’s electric power control system broke down and with it the Castle’s. Soon everybody was hitting the woods. The problem went on for two days...no juice, no pumps, no water, no flush toilets. Nobody seemed to be either interested in, or capable of, fixing the problem.

I volunteered to take a crack at troubleshooting the electrical control board for the generator. It was located in a 10 foot by 10 foot brick building on the Castle's Estate grounds. After I got the keys for the place from the engineers, I opened the door wide to let in some sunlight so that I could see what I was doing. I rolled up my sleeves and went to work for the next several hours.

Using a Weston volt-ohm-meter I recently salvaged at an Army Depot in Normandy, I reconstructed a schematic diagram by tracing the wiring on the control board. Once I finished that and had figured out what the board was supposed to do and understood how the components were meant to operate, I started troubleshooting it systematically.

The control board was made up of a vertical 4 foot by 4 foot black, hard rubber panel. Mounted on it were a number of ordinary relays and several time-delay relays. These were true museum pieces even then. They consisted of a solenoid driving a rack-and-pinion; the pinion in turn rotated a small propeller. Changing the pitch of the propeller blades changed its wind resistance and hence the time it took for the solenoid to fully suck in its armature and, finally, close some contacts! Those relays looked like French predecessors of relays Edison built years later.

After a few hours of troubleshooting, I found the problem. It turned out to be a wire that was stretched across the board between two terminals. The wire had broken but the break was hidden from sight by a sleeve around the wire of varnished cambric insulating tubing. I found it by making measurements between all points until I got an open-circuit indication where there should have been a direct connection according to my schematic. Then it was just a matter of putting a new wire in its place, flipping the power switch on.

Bingo! The latrines worked again! I was the local hero for the day.