Noob wiring question

[Beachbummer]

So normally the engines are grounded...is that ground lead also switched? I am also challenged in understanding why it may be a problem as long as ALL connection to the battery ground is disconnected... Still seems iffy, but would like to actually grasp why.

 

[MidnightRider]

So normally the engines are grounded...is that ground lead also switched? I am also challenged in understanding why it may be a problem as long as ALL connection to the battery ground is disconnected... Still seems iffy, but would like to actually grasp why.

No typically in a DC system (boat, car, etc) the ground is not switched, all loads and switches are the positive side. Although there are some autos out there I know at least in the past that were "postive grounded" systems but that is not relevant. Its a normal convention for DC to be this way to avoid confusion for working and maintaining the systems. Sounds like there may be a deeper reason for the convention being this way (per @jb32566 comment)? Outside my knowledge base so others can add to that.

 

[MidnightRider]

Certainly 120V will conduct in water, but low voltages like 12v dont. Unless you have enough conductive materials in it (like saliva does).

If I remember my Physics correctly from way back when, it also makes a difference on the content of the water (i.e. high in minera content conducts better than distilled water)

 

[Beachbummer]

I meant, in this boat's case that has this odd wiring...Is the engine connected to the negative pole while the switch is in the off position?

 

[Gym]

Yeah 120V AC is a totally different animal than 12v DC

Stick the bottom of your tongue across the terminals of a 9v battery. I dare ya.

 

[MidnightRider]

Stick the bottom of your tongue across the terminals of a 9v battery. I dare ya.

Only if you stick your tongue in a in a light socket - I dare you! I stand on my statement, “totally different animal”

 

[Beachbummer]

Voltage and Amperage are 2 different animals. DC vs AC also plays a part. Some time ago I bridge the battery terminals with pliers and through my graduation ring... After the sparks hit, my ring got so hot I removed it in a reflex and threw it about 50 yards away. Until I lost it you could see a melt dent where it had bridged with the pliers!....Electricity is no joke even at low voltage. But its the watts that kill you (Volt x Amps)

 

[jb32566]

i couldn't find the one i was looking for, but i remembered a poster on the wall when I was an undergrad that was similar to what's here.
Electrical Safety: The Fatal Current

 

[BlkGS]

Stick the bottom of your tongue across the terminals of a 9v battery. I dare ya.

Saliva isnt water is the key difference.

 

[BlkGS]

After my test run today, i ended up rewiring with the single path switch. Hooked the motors direct to the battery... they have ignition switches that yurn them off anyways. Will add the dual path switxh later anyways.

Sadly, all my wiring was for nought. My new radio was DOA. Pops the breaker when it turns on.