Electricity During Sinking

[Gloria Lyons]

I have always wondered how the electric lights remained on during the sinking of the Titanic. I understand that crewmen kept the electric generators running as the ship sank. My question concerns the dangerous mix of electricity and salt water. In every film or artist's renditions of the sinking, the lights remained on until the ship finally sank. I would have assumed that as soon as the water level filled the bottom of the ship from one end to the other, that every electrical circuit in the ship would have shorted out. Even if that did not happen, then the water would have extinguished the generator boilers and there would have been no electricity at all.

Any insight or answers would be greatly appreciated.

Thank you,
Gloria Lyons

 

[Paul Rogers]

Hello Gloria.

I believe that the answers to your questions lie in the fact that Titanic sank slowly by the bow. Until she broke up, the stern of the ship was watertight. In fact, boiler room 4 didn't flood until about 2.00am, when the end was very near.

Therefore, you had boiler rooms 1, 2 and 3, and all compartments further astern, all watertight and free of flooding until the ship broke up. Thus, there was power available to keep the lights burning.

When the ship broke, the keel collapsed around the bulkheads either side of boiler room 1. This would have destroyed the watertight integrity of the stern, as well as severing the electrical cables and steam piping. So, at that point, the lights went out!

Hope this helps!

However, one thing I've always wondered about is how long the lightbulbs remained alight underwater. I've read in many books stories of how the bulbs continued to glow, even in the flooded compartments. I wonder:

(1) How deep would the compartments have to have been, before hydrostatic pressure imploded the bulbs?

(2) Why didn't leakage simply short-out the light fittings?

(3) If some bulbs did short-out, why didn't this take out the whole of the ship's lighting system, (like a blown bulb could also burn out a domestic main house fuse)?

Any electricians out there who can help?

Regards,

Paul.

 

[Dave Gittins]

Paul is right about the area needed for power generation not flooding till the very end. The boilers in stokehold 2 supplied steam and the engines that drove the generators were right aft. There were also emergency generators on a higher deck. One of those was used also.

I think the lights that were seen underwater were simply in cabins that had not yet flooded. The weight of water tipped the bow down and cabins with closed portholes stayed above the waterlevel for a time.

We need a real electrician here, but I would think that everything was wired in parallel, with plenty of fuses or circuit breakers. You notice that when your toaster burns out, you might blow a fuse in your house but you don't black out the neighbourhood. Failed light globes don't even do that, because they don't cause excessive power to flow. Titanic was very well designed in this respect. They knew the value of what we now call redundant systems and used them wisely. There was even a complete emergency lighting system which could only be accessed by authorised crew.

 

[Gloria Lyons]

Thanks Paul and Dave. I didn't know that there was an upper deck emergency generator that was actually put into service. Paul actually posed three questions that have always been in the back of my mind. I also wonder if the rather primitive electrical engineering of the early 1900s didn't contribute by accident rather than by design to the lights remaining on. I believe that modern day electrical circuits would blow instantaneously at the first moment of water contamination in an effort to prevent accidental electrocution.

For some reason or another I have always found the subject of the lights remaining on very fascinating. Yet...I have never read or heard much discussion on this subject.

Thanks for your previous responses.

Gloria Lyons

 

[Martin Pirrie]

As an electrical engineer, the electrical and the radio equipment are my speciality - here goes!

The Titanic had 4 main electric generators each rated at 400kW: 100 volts DC. Each generator had its own steam engine. There were also 2 auxiliary generators. These were rated at 30kW each and were fitted on a raised platform some 20 ft above the water line in the turbine engine room. The auxiliary generators were to be used in an emergency or when the main genarators were out of action. The auxiliary generators were switched in and out of circuit manually.

The auxiliary generators were connected to, amongst others, 500 lamps fitted throughout all passenger, crew and machinery compartments: cargo & gangway lights: lights on the bridge: navigation lights, wireless equipment and 4 boat winches on the boat deck. The wireless room had a 5kW motor generator and a further independent battery supply.

If someone switched on the auxiliary generators, then there would have been power for a few minutes longer as the ship sank.

 

[Martin Pirrie]

I have found some more information. From The Daily Mail newspaper dated 20 April 1912: "Oiler A. Whyte states that shortly after the accident the emergency dynamos were started..."

Second officer Lightoller stated that when he was in the water he watched as the ship began to sink. When the second funnel aft reached the water the ship was perpendicular. "There were no lights burning then, though they kept alight practically to the last."

 

[Gloria Lyons]

Thank you Martin. I always suspected the ship was on DC power rather than AC. I have never read of any reported electrocutions, and the DC power would account for this. I would tend to think that if the ship had AC power, several of the passengers or crew would have been electrocuted when coming in contact with standing salt water.

Many thanks,
Gloria Lyons

 

[Martin Pirrie]

Dear Gloria,

Please don’t think that you can’t be electrocuted by DC! I speak as one who was thrown off his feet by trying to disconnect a DC motor whilst it was still switched on! However, the steelwork of the ship wouldn't become "live". But I suppose one could get a shock from a piece of electrical equipment not properly grounded.

Much of the T’s switchgear was provided by a company named, then, Dorman & Smith Ltd from Manchester, England. The company still exists. They’ve dropped the ampersand and call themselves Dorman Smith Ltd. now.

The protective devices, be they wire fuses or circuit breakers would have operated when the sea water came in contact with the cabin switches, lampholders etc.and each deck would be switched off as T went down. There could have been some sparking and spluttering at the device before the fuse blew as the water splashed about. I have no record that any one mentioned this.I can imagine that the lights could have remained illuminated for a short time after the water covered them (short time means a few seconds) before the fuses blew. A DC supply is more difficult to switch off than AC and the DC current would flow for a little longer time than AC under the same conditions.

 

[Josh Geurin]

hi im also very interested in the lighting on the ship. Im sure since the system was dc and not ac the lights where able to burn longer. take a boat trailer for example, when I dunk my trailer into the water at night i leave the lights on so it is easy to so it in the water. And they burn just fine, even for up to half an hour. I know that the fixtures I have arnt sealed so the are geting wet. I have a '99 ford f150 and the breakers have never triped when doin this.

I do understand that the wireing on my car and the wireing on the Titanic is very differant. But i have done many experiments with dc circuits underwater, and most work fine. One note though they will carode after time. But this time is much longer than the time for the ship to sink, so we know that carrosion didnt effect the ships lighting while sinking.

In the movie (97 Titanic) there is a part where crew men are in a room with circuit breakers. In the movie one of the men yells "shut all of the breakers, shut them" I guess they where turning them back ON as soon as they turned off (triped) from the circuits geting wet. Just wondering if that really hapend the night of the sinking.

 

[Michael H. Standart]

Josh, since none of the people from the electrical switchboard spaces survived, we'll never know exactly what they said or did...beyond keeping the power going until the very last.

BTW, I think you may have crossed a wire or two on the quote. I remember a stoker crying "Shut all the dampers! Shut them!" in the boiler room scene portrayed at the time of the collision with a certain overgrown icecube. I'll have to reveiw my copy of the movie to get the lines spoken in the switchroom. It's not high on my list of priorities as two books I ordered from Amazon.com on the Titanic are on the way! I expect them to arrive in the next day or two.
Cordially,
Michael H. Standart

 

[Martin Pirrie]

Josh, I'm a bit late on this one. Many of the light fittings seen illuminated on T would have been deck fittings and would have been waterproof. These could well have been lit underwater for a short time. I believe that we have all seen modern cars under water after a flood with the headlights on. Same sort of thing, but with sealed headlights. As long as the external water pressure is not great enough to force water through the various weak places, cable entries are the most likely, the lamp will remain iluminated.

The generators on T would have been big with,large empty spaces in the frames to get the air in to cool the windings. Modern electrical machines, are often totally enclosed because of better isulants and although not sold as being waterproof, will survive an underwater trip from time to time! In fact the difference between a modern waterproof electrical machine and a totally enclosed one is often only an extra gasket or two on the jointing surfaces.

 

[Stephen Hinkle]

I know some other data from a physics experiment I did in a science lab at San Diego State University.

Basically, in my lab experiment, we measured water tempature by putting a resistor inside the cup filled with water, and saw how long it took to rise the temp. We used a DC Power supply for this. How does it relate to the situation here, you wonder?

Well, I found out that water is a conductor of electricity, but not a very good one. Well, the light bulbs (before they broke) provide some RESISTANCE, so the bulbs were NOT in a dead short, until the bulbs and cables broke. In addition, water provides resistance too.

So this resistance probably lowered the current and the shock risk to passengers. Resistance lowers the amperage of the current being sent through the line. It is CURRENT that kills, not voltage.

In addition to the backup generators, it is possible that there were some lights that ran on batteries, so they would stay on, while engines are starting, or in case they stop for some reason.

 

[Dave Gittins]

On page 123 of The Birth of the Titanic you can see the very open windings Martin is talking about.

Providing power was not a great problem right to the end. All the generators were well out of harm's way in the stern of the ship and the Scotch marine boilers have the property of maintaining a supply of steam long after the stokers quit. Those in boiler room two would have been going to the end.

I mentioned elsewhere that Chief Electrician Peter Sloan seems to be among the unsung heroes of the night. He and his men must have done wonders as the various circuits failed. Also, give some credit to those who designed the wiring.

Stephen, try repeating your experiment with seawater. Pure water is indeed a poor conductor, but salt greatly increases conductivity.

 

[Stephen Hinkle]

Dave,

I know salt increases connectivity, but the bulb still being on, decreases the current nontheless, because it is a parallel circuit.

 

[Raymond Leggs]

Well if you plug a bulb into a wall socket adaptor it
let it burn until it gets hot
pour water on it it
the bulb will blow open and it
will catch on fire and go out
why does it blow up
Did you know that some of the titanics light bulbs are intact and untouched by corrosion?