electricution in an electric boat

[eastern270]

does anyone have any idea what would happen to a person or persons in an electric(battery) powered boat if it swamped or capsized. What is the possibility of being electricuted ? power example we'll assume to range from 24-120vdc.

[Buddy]

That's a high range to assume. I think 36 DC volt drive systems are as high as you usually see, I've only heard of 48. Thats below what it takes to go through skin. I think a burn injury is far more likely.

[Dave Lesser]

Solomon Technologies uses 144 volts DC and Elco uses 72 volts DC for their largest motor. Don't you have to participate in "completing the circuit" to be electrocuted?

[Venchka]

Dunno about all that, but I do know that one 12v automotive battery has sufficient amperage to weld a 1/2" open end wrench to the fenderwell of a 1978 Oldsmobile Cutlass.

Wayne
In the Swamp.

[Nicholas Carey]

Originally posted by Venchka:
Dunno about all that, but I do know that one 12v automotive battery has sufficient amperage to weld a 1/2" open end wrench to the fenderwell of a 1978 Oldsmobile Cutlass.

You're not going to regale us with the tale of how you acquired that knowledge?

[Alan D. Hyde]

C'mon, Wayne...

Alan

[Venchka]

Nope. I wasn't there. You can't prove a thing.

Accidentally dropped the wrench. One end landed on the (+) post of the battery and the other end landed on the fenderwell. The resulting arc was impressive. I swatted the wrench. It moved and broke the circuit. The wrench still has a chunk of Cutlass attached to it. All of this happened in about half a nano second. Disconnect the battery if you're wrenching in the neighborhood!

DOH! What I meant to say...cover up the terminals...

Wayne
In the Swamp.

[ 04-04-2005, 04:16 PM: Message edited by: Venchka ]

[ssor]

Back in the dark ages when many farms were run on thirty-two volt DC there were reports of people being killed with that voltage in wet conditions. As I recall it only takes about fifteen milliamps to shut you down. Electrocution in the water usually causes death by drowning. Stray current in marinas has been said to result in drownings of competent swimmers.

[htom]

The possibility ranges from very small with dry skin and insulated contact to Murphy-guaranteed certainty if you don't plan for it!

[RonW]

CRISPY CRITTERS- FRIED BEYOND RECOGNITION.-

I am pretty sure that nothing happens, I agree with Dave, you would have to make the circut complete. Or you would literally have to grab hold of the positive connection to make a circut.
The water wouldn't become electrified, nothing happens when someone drives their vehicle into the river or lake. The vehicle does not conduct the battery voltage, but if you where to stand in the river and touch your positive cable, that might be another thing.

There are 1,000's of electric boats, and elco uses a 48 volt system, so why has no one been electricuted, because we have yet had a flooded boat with some one stupid enough to grab the end of the positive cable at the same time they where sitting in water. In fact (not sure) but they may have to grab the negative cable also at the same time to get a proper ground.

[Venchka]

Volunteers, anyone? For the sake of science?

Where's Chuck? He'll know.

Wayne
In the Swamp.

[Norske3]

What Venchka said....welding a vise grip to the underside of the trunk...only it was a 1970 Plymouth.

[Ian McColgin]

If it's salt water, a high resistance circuit will be completed between the battery poles and nearby fish will be fine. The battery will likely be ok as well if it's a sealed unit. If not a sealed battery, you may have a chlorine gas problem and the acid will surely be contaminated.

[Venchka]

Originally posted by Norske3:
What Venchka said....welding a vise grip to the underside of the trunk...only it was a 1970 Plymouth.

Welcome to the club! Got your attention real quick, eh?

Wayne
Quit his welding job after half a second In the Swamp.

[hikingchrs]

Internal resistance between your ears is about 100 ohms. E/R=I 12v/100ohms=.12A. takes .0005A(5 milliamps) to kill irrc. other bad ways to complete a circuit is hand to hand apply voltage across the heart... left hand to right foot again volt across the heart. to a lesser degree right hand to right foot, or left hand to left foot.
Chris

[Meerkat]

Voltage does not kill - amperage does!

While the inter-ear resistance might be only 100 ohms (I dispute this in the case of vacuum heads! ), skin resistance is generally higher. Although a charge as low as .5 milliamps _can_ kill, 10-15 milliamps is where it starts to get more reliably dangerous. As noted above, it does depend on the path through the body.

Always use the back of your hand to test a circuit - the involuntary muscle contraction will pull your hand away if the circuit is live.

[werner]

not 100% sure but never test a circuit with your hands.Low voltage can be deadly in the "right " enviroment. I believe DC electrocution doesn't make musscles contract like AC does (on certain frequencies).
anyway, metal seawater and a bank of batteries in't the safest enviroment.
There is a difference in the effects DC has on the organism.
Read a long time ago on a warning sign that beeing electrocuted with DC has some effect on the blood's capacity to transport oxygen and a urgent transfusion has to be given as first aid so the treatment is different from an AC electrocution ? Perhaps it is not a bad idea to get some medical info on that DC first aid subject just in case.
But anyway dropping a tool on the terminals is a dangerous and pehaps a more frequent accident since massivly shortcircuited batteries tend to explode.(Working on batteries: Also remember to remove the wedding ring from your finger or put insulating tape around it)

regards,
werner