# Electrical shocks occuring on the ship



## Navyguy

Does this happen when the ship is on shore power? I assume there are separate generators that are running separately from the engines when at sea?

Cheers

John


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## syed.nifty

Hi there,
We havent connected to the shore power. Supply is either from two generators .
There is junction box for accomodation lighting load. So i have switched this breaker and saw that 2.7 volts disappear. Anyways i still have to see whether the static electricity still exists or not.


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## backstay

What's the floor covering? 2-3 volts is not going to give you a shock.


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## syed.nifty

Hi, the accomodation floor has mat.


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## backstay

syed.nifty said:


> Hi, the accomodation floor has mat.


Fiber or rubber?


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## Wiresmith

check that the generators/electrical system is electrically bonded to the ship. not just the frame of the generator but the electrical system itself, us on land call it the main bonding jumper it connects the grounded conductor("neutral") to "ground" (which in this case is the ship). and all separately derived systems (transformers), you can check with a wiggy(solenoid style voltage meter) and check voltage from a phase to ground on each separate electrical system. i don't know anything about ships specifically.


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## telsa

I'd bet that the static electricity is coming off between your own body and the ship.

It's rebuilt as you walk across the floor.

I experience the exact same effect working around my pick-up truck... after squirming in a cheapo plastic chair. 


You wouldn't just happen to have such chairs in the accomodation section ?


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## hardworkingstiff

I picture metal doors and bulkheads. So I'm curious when you measure 2.7 volts from the door handle to ground where are you getting the ground potential (assuming the ship is metal, including the door and door handle). If I'm mistaken about the construction please advise.


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## MechanicalDVR

hardworkingstiff said:


> *I picture metal doors and bulkheads.* So I'm curious when you measure 2.7 volts from the door handle to ground where are you getting the ground potential (assuming the ship is metal, including the door and door handle). If I'm mistaken about the construction please advise.


Great question!

The doors should be grounded to the hull of the ship via metal to metal contact throughout the ship.


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## syed.nifty

Hi all,
I appreciate for all responses.
Firstly the carpet is thick foam type carpet, as it cant be fiber nor rubber.
The door frame and door handle is metallic, also the door has metallic border but its wooden remaining.
All the doors handles show almost 0 volts except one particular door which has 2.7 volts. 
Its static current occuring in all the door handles for anyone. This problem had started recently. 
As we dont have wiggy tester here except normal multimeter. I will test the phase to earth voltage at the generator output.

Thanks


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## dronai

Fake !! Keep em thinking syed nifty , lol


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## Southeast Power

I'm not convinced every ship has a grounded system or if it would even matter.
The problem is static electricity, he just described the carpet.
The only difference in potential is hand to doorknob, it's a people problem.

There must be a way to mitigate this that someone in the boating world knows about.

Tesla might pop in later. He designed and installed the anode system on the QE2.

Nothing going on here. :thumbsup:


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## hardworkingstiff

syed.nifty said:


> Hi all,
> I appreciate for all responses.
> Firstly the carpet is thick foam type carpet, as it cant be fiber nor rubber.
> The door frame and door handle is metallic, also the door has metallic border but its wooden remaining.
> All the doors handles show almost 0 volts except one particular door which has 2.7 volts.
> Its static current occuring in all the door handles for anyone. This problem had started recently.
> As we dont have wiggy tester here except normal multimeter. I will test the phase to earth voltage at the generator output.
> 
> Thanks


Only 1 handle with voltage, interesting. What's different in that area?

On that 1 handle, where are you reading the voltage? From the door handle to .... ? (I know you said earth ground, but I can't figure where physically you are reading the earth ground). 

If it is static electricity, you should be able to discharge the static and then not read the voltage. If it is induced somehow from the wiring, then you won't be able to discharge the voltage and you will always read voltage. 

Please let us know where your test leads are landing when you read the 2.7 volts.


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## hardworkingstiff

Southeast Power said:


> I'm not convinced every ship has a grounded system or if it would even matter.
> The problem is static electricity, he just described the carpet.
> The only difference in potential is hand to doorknob, it's a people problem.


 I don't know how you can make that determination w/out knowing where the leads were landing to read the voltage.


> Tesla might pop in later. He designed and installed the anode system on the QE2.
> 
> Nothing going on here. :thumbsup:


^^ Funny, :thumbsup:


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## Southeast Power

hardworkingstiff said:


> I don't know how you can make that determination w/out knowing where the leads were landing to read the voltage.
> 
> ^^ Funny, :thumbsup:


It's simple static.
OP mentioned the carpet.
That 2.7 volt reading is meaningless. You couldn't feel that and most digital meters have ghost readings.

I standing on my carpet theory.


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## hardworkingstiff

Southeast Power said:


> It's simple static.
> OP mentioned the carpet.
> That 2.7 volt reading is meaningless. You couldn't feel that and most digital meters have ghost readings.
> 
> I standing on my carpet theory.


OK, but where do you believe the leads were landing in order to read the voltage?


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## syed.nifty

Hi all,
Once again, i appreciate for everyone's responses. The 2.7 volts is coming from the door handle to the ground which is the body of the ship. This occuring in the accomdation area, and in one door and for the others its zero. But the static is there in all the doors of the accomdation. As i switched of the main breaker in accomodation, the 2.7 volts disappears.
But i find something interesting. There is 110 volts 3 phase which is coming from 440/ 110 transformer . so i checked phase to ground, and i get some voltages in two phases but in one phase there is no voltage. That phases is getting grounded. I checked the 110 transformer which is giving out to 3 breakers. One breaker is for the engine room , another for accomodation and the last one is wheelhouse. So when i switched off, the engine room breaker, then its showing voltages accross 3 phases when connected to ground. So that means, there is ground something in engine room breaker and thats why its making one 110v phase grounded.


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## Navyguy

Ships don’t have “grounds” or even “neutrals” for that matter...

Older ships will have 60 volts phase to phase for what appears to be 120 volts, but not like the 120 volts we see ashore.

Newer vessels will have generators that will produce 120 volts on a single line; similar to what we have on shore, but there is no bonded neutral and the only reason they have that is because they will connect to shore power; makes for phase synchronization easier when they do the transfer and don’t “black out” the ship. If the vessel is not equipped with shore power connections then it is likely 60 volts phase to phase with no “ground” or “neutral” as we know it ashore.

There is likely voltage running all over the ship but as you touch something is dissipates. If something “shorted out” it would have to be phase to phase only. 

Cheers
John


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## Southeast Power

Not a ship electrician by a long shot but,
Some have a delta system that isn't grounded but should have two or three lights, one will come on if you have a phase to ground problem.The fact that you can control the "door voltage" problem somewhat indicates a ground.
The puzzle is of course how you are feeling 2.7 volts


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## hardworkingstiff

Southeast Power said:


> The puzzle is of course how you are feeling 2.7 volts


I once responded to the gangway (aluminum) shocked someone (floating dock).

I tested from the gangway to the water and found 1.2 volts AC on it. I didn't think that was anything to shock someone so I grabbed the gangway with one hand and stuck the tips of my fingers into the water with the other (yea I know, across the heart, dumb move). 

Well, no shock. So I submerged my hand farther with no feeling until I hit a cut I had on my hand and I can tell you that I did feel it when my cut went under water. So, while I agree with you shouldn't be able to feel it, my personal experience says otherwise.


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## syed.nifty

There is one phase cable burnt and its grounded. We can hold handle which has 2.7 volts but there is static still in this handle and the other handles. Maybe after changing the burnt cable , we might not get the static. 

Thanks.


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## syed.nifty

Hi All
There was one1.5 wire for the socket which was ground. After disconnecting this socket from 110v supply, the phase which was grounded became normal. 
And also, there is no more the static on any of the door handles. The 2.7 volts came to 1 volts. Thats okay , as there is no more shocks.
Thanks


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## hardworkingstiff

syed.nifty said:


> Hi All
> There was one1.5 wire for the socket which was ground. After disconnecting this socket from 110v supply, the phase which was grounded became normal.
> And also, there is no more the static on any of the door handles. The 2.7 volts came to 1 volts. Thats okay , as there is no more shocks.
> Thanks


If that is a "phantom" 1 volt I agree that it is not too much of a concern.

Now, if you test it with a low impedance meter or a high impedance meter in parallel with a low impedance jumper, then I would say there is something still not right. Whether or not you should be concerned is ... ?

Edit: I do not believe static was ever the source of that voltage.


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## Trailboss

Use an analog meter, you get some erroneous reading on DVM at times. (even expensive Fluke meters). You say you measure 2.7 volts with earth? Vessels don't have earths. And are you measuring AC or DC?


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## Bird dog

Trailboss said:


> Use an analog meter, you get some erroneous reading on DVM at times. (even expensive Fluke meters). You say you measure 2.7 volts with earth? Vessels don't have earths. And are you measuring AC or DC?


This is an old thread & the OP last posted September, 2017.


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## max-8988

is there any insulation on the ship?


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