See full version: How to Wire a Switch With White, Black and Ground Wires
Connect the black wires to the switch terminals. The switch simply interrupts the current so it doesn't matter to which terminal you connect either wire. If the switch has self-clapming holes behind the terminals, insert the end of each wire into a hole. If not, bend each wire clockwise, hook it around a screw and tighten the screw, using a screwdriver. here
The hot wire in a 120-volt residential AC circuit usually is coated with black insulation, while the return, or neutral, wire is white. A single-pole, single-throw switch — such as a light switch — works by interrupting the hot wire, so it has two brass terminals for the hot connections and no silver terminals for neutral. Hooking up a switch is the essence of simplicity. You connect the black wires in the electrical box to the switch terminals, and the white wires to each other. The switch also has a green terminal for the ground wires, which usually are bare. here
Splice the white wires together by twisting the ends together clockwise, using pliers. Screw on a wire cap to hold them together and insulate the ends.
Feed the circuit cable through the back of the switch box and pull out about 6 inches of slack. Run another cable of the same gauge to the fixture you want the switch to control. Feed the end of that wire through the back of the box and pull out the same amount of slack. [links]
Cut the plastic covering off of the ends of the cables, using a utility knife. Pull the wires apart. Trim 1/2 inch of insulation from the ends of the black and white cables. [links]
current to flow. If a second earth fault occurs, then the two earth faults together would be equivalent to a short circuit fault ( via ships hull) thus resulting large current would operate the protection devices, cause disconnection of, perhaps, essential services creating a risk to the safety of the ship.
A basic circuit consist essentially of Two parts:
Only 2 types of circuit faults can occur. Either break in the insulation or break in the conductor. more
The requirement ashore is the safety of human beings. So, inorder to prevent human-electrical accidents, the neutral is earthed. The priority is neither the safety of the machinery nor the continuous necessary operation of the machinery. But the scenario onboard ship is totally different. The priority is the continuous operation of the machineries which are classed “essential”. The distribution system followed onboard is “insulated neutral” system. The main priority onboard is the safety of ship which includes navigation & fire safety..etc. If due to earth fault, the machinery classed as"essential" gets isolated, say for eg: steering gear, then the safety of ship is at question, which may lead to collison, grounding, fire & pollution etc..So the priority onboard ship is to maintain the continuity of the supply to the machinery in the event of “single earth fault occurring”.
If the earth fault occurs in “insulated neutral distribution system”, will not cause any equipment to go out of operation and thus maintains the continuity of operation of the equipment. This point is to be noted," the machinery still continues to operate". Thus a single earth fault will not provide a complete circuit for the fault
The break in the conductor leads to non-flow of current in the circuit. A break in the insulation leads to an earth fault, allowing the conductor to touch the hull or earthed metal enclosure. more
Sometimes the silts might get trapped, and they clog the passes or even the heat exchanger. You will have to clean those up if the situation arises.
At times this method might prove to be counterproductive, but the situation might be such where you wouldn’t have much of a choice.
The depth of the water is something to think of when weighing your options, as the depth will have a significant impact on your situation. It will also help to analyze the situation and pick the route out for you. here
There are some tactics and methods you can employ, which will help get the boat out on the ground But you also have to consider which of these options will have the least risk. You will be able to choose the option based on the risk. here
When selecting the grounding method on ship the primary factor with the selection is the safety of people and secondly the safety of equipment. But loss of vital equipment can endanger a ship’s safety and this in turn can reduce the safety of the crew.
Although “ungrounded ” there will still be a fault current flowing due to the capacitance of the cables and interference suppression capacitors fitted inside equipment. In large installations with many cables this fault current can be substantial. more
The main cause of faults on board of a ship are ground faults which occur when live conductors come into contact with the ” ground “.
I spent two years putting a meter on every boat that was hauled for survey. The average boat generates about 1/4 volt DC current and going as high as 1/3 volt without causing damage. But when it gets up to 1/2 volt, you got a problem. Zincs will erode rapidly and underwater metals begin to be affected. more
No one who is not trained in marine high voltage systems should ever perform wiring on a boat. The potential for creating deadly system faults that are injurious to both people and the vessel itself is too risky. That includes something as apparently simple as wiring a new service outlet, for if you don't understand the principles of the system, you are likely to unknowingly create a problem. Just because you know how to do wiring around the house, doesn't mean you know what you're doing on a boat.
Your Bottom Paint
What does bottom paint have to do with electrical systems? Nowadays, with copper based paints, a lot. If, the next time your boat is hauled and you see large ugly burn patterns around all your underwater metals, you got a stray current problem. Copper-based bottom paints react severely to stray current, and serves as a great indicator. Sort of litmus paper for electrical problems.
Bonding Systems
Bonding simply means wiring all the boats underwater metals together. This is done because of the galvanism caused by the different metals. By wiring them together, the differing potentials are equalized. Bonding does not solve problems of galvanism or electrolysis, but it does spread the the flow of current around over more metal, so that 1/4 volt or so won't cause any damage. Whereas if that 1/4 volt were going to one small seacock, it would probably eat it up in a hurry. In other words, bonding lessens the effect of small amounts of current. On the other hand, it also spreads it around to all underwater metals so that higher currents end up damaging everything.