Topic: why am I getting a shock in my boat

[Tunacious]

While fishing in Port Orford for salmon I noticed that when I shut off my wash down pump if I had my other hand on top of my aluminum fish box the hand on the fish box would get a shock.

The fish box has a pump attached to it to pump the water out but there shouldn't be any electricity going to the box that I know of.

I don't know much about electricity but it would appear to me my body was being used as the ground for the wash down switch because I was wet and perhaps I was a better ground than the wire going to the battery.

The switch is grounded.

Anyone who can tell me what is going on I would appreciate it.

I am attaching a photo of my boat which shows the aluminum fish box in the middle of the boat that I am speaking about.

[Hydroman]

Is you fish tank bonded to your electrical system,  if not it my be static electricity. 

Hard to believe that you would get any shock from your 12 v system.

Was your inverter on when you felt the shock?

Jim

[Tunacious]

The box has a pump hooked to it that when I turn on the pump it will pump water out of the box.  The pump is grounded to the battery.

You asked if my alternator was on???

Im not sure what your asking Jim.  The boat was on and trolling when this was happening.

I turned the switch on and off three different times with my hand on the box until I decided that was enough.

If I didn't have my hand on the box I didn't feel a shock when I turned the wash down pump on or off.

[DevMah]

Tunacious

Just need to clarify...
one hand on the pump switch for the wash down other on the aluminum frame of the fish box. You only feel the zap when you turn off the switch?

How old is you switch?

Few guesses ...
 inductive spike... if your switch is worn, old possibly cracked...replace the switch.

 Or Try installing a shunting diode aka fly back diode. Make sure the diode polarity is reversed when installing across the motor.


https://www.westfloridacomponents.com/blog/inductor-need-fly-back-diode/


Dev

[Tunacious]

Switch is only a year old.

The inductive spike sounds like is what happening to me.

This sucks.  Just when I got the courage up to rewire my boat I find out how much I don't understand.

Thanks DevMah

[StreamFixer]

Static Electrical shock was the first thing through my mind...  You need to quit dragging your feet across the carpet Walt... 

StreamFixer

[Croaker Stroker]

Static....ground the tank. While you’re at it, ground any metal gas tank fillers.

[First Cabin]

Tunacious

Just need to clarify...
one hand on the pump switch for the wash down other on the aluminum frame of the fish box. You only feel the zap when you turn off the switch?

How old is you switch?

Few guesses ...
 inductive spike... if your switch is worn, old possibly cracked...replace the switch.

 Or Try installing a shunting diode aka fly back diode. Make sure the diode polarity is reversed when installing across the motor.


https://www.westfloridacomponents.com/blog/inductor-need-fly-back-diode/


Dev

Thanks for the education!

Tunacious, what brand and model of switch are you using?

[Danno]

Get a marine quality switch:

https://www.bluesea.com/products/7929/Contura_II_Switch_SPST_Black_-_OFF-ON

[Tunacious]

the switch Im using is a seadog 420396-1

https://www.amazon.com/420396-1-Splash-Garde-Off-Switch/dp/B001BW6BJK

[Threeweight]

That looks like a basic metal automotive push-pull switch with a plastic boot over the wires.

I agree with Dan, go with a Blue Sea product of some kind.  In applications like this, plastic is a good thing.

[DevMah]

the switch Im using is a seadog 420396-1

https://www.amazon.com/420396-1-Splash-Garde-Off-Switch/dp/B001BW6BJK

This switch is only splash resistant at best rated ip64 (no rating on Sea Dogs web) a plastic switch would be better.

I recommend you to go to a ip67 rated switch, or min ip65 ...the switch Danno has recommend would also work fine.


https://www.bluesea.com/products/4303/WeatherDeck_12V_DC_Waterproof_Switch_Panel_-_2_Position

FYI ip ratings

http://www.rainfordsolutions.com/ip-enclosure-ratings-and-standards


Dev

[Rokefin]

 

Great info, copied and put  in my boat file for later use.

[Tunacious]

Great Info

Ive decided Im going to go with all blue sea electronic switches when I rewire my boat.  I used Blue sea switches when I installed on shore power in my boat and It is awesome.

Im wondering if I am able to, or need to replace the main panel switch next to the helm with a blue star panel.

[Threeweight]

My old 17' (a 1989 hull) just had a bunch of toggle switches mounted in round holes on the dash when I got it.  I cut a big square hole and replaced all that mess with a Blue Sea "Weatherdeck" switch panel:



These are nice for a variety of reasons, a big one being that you get a fuse for each switched load, which simplifies wiring and makes it easier to troubleshoot on the water.  Also simplifies wiring your anchor/nav lights, and they are pretty water/corrosion resistant.



I believe the individual switches are modular, and can be removed and replaced if you need (so a simple "on/off" can be swapped out for a 3 way switch, or a momentary on switch.)