Getting shocked with engine running

[Capt Len]

I don't see you need a closed circuit in the usual sense for a static discharge into capacitive body. It simply is a pile of electrons trying to get to somewhere they are not. Need measured in volts, flow measured in coulombs per sec or milli amps and the body they run into in farads WE all need a good jolt now and then.

[davidpm]

I'm just using some imagination here. I'll try to put together a circuit to test my theory.

The bow light short and the binnacle short might be the following.
Bare hot wire touches stainless tube.
Stainless tube is connected by bonding or another bare wire that may have been that way for months.
Current flows through circuit that includes the stainless but with sufficient resistance to prevent the breaker from blowing. Don't forget if you connect a wire directly from positive to negative on the battery the wire will melt unless there is a fuse or breaker which opens instead. There has to be enough resistance so fewer amps flow through the circuit than the rating of the fuse.
You put your wet hand on the stainless and if the resistance of your hand is lower than the stainless the current flows through your hand producing the shock.

To test this I have to get a length of metal and wire it in a circuit, hopefully with a fuse for safety and see if I can get a shock with one hand.
I have an old bent boom, not sure I have any stainless, will have to look.

[bgeddes]

I don't see you need a closed circuit in the usual sense for a static discharge into capacitive body. It simply is a pile of electrons trying to get to somewhere they are not. Need measured in volts, flow measured in coulombs per sec or milli amps and the body they run into in farads WE all need a good jolt now and then.

A coulomb per second is equal to an ampere.

The static is has enough voltage to overcome the dielectric constant of a distance of air. The higher the static charge, the further it will jump to provide the aforementioned shock. The circuit is complete, part of it is air.

[Izzy1414]

Originally Posted by notmuchforwriting

If anyone has a better explanation how my hand “completed the circuit” I’d like to hear it.

Yes, you have to complete the circuit ... but with static electricity, the rather simple circuit terminus are two oppositely charged bodies - you, on the one hand and the doorknob/bow rail/binnacle on the other.

[AdamLein]

Hm. I usually take the term "circuit" to mean a closed loop. A single static discharge doesn't involve a closed loop.

An electrical potential difference between two points will drive a current between those two points, regardless of whether the two points are on a closed loop.