auto bilge pump

TJAGAIN

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i have a spare bilge pump and a separate float with it. not wanting to just leave it in the garage i thought i could wire it up with it's own battery along with ma solar panel. can anyone help me with a wiring diagram for wiring the float to the pump?
 
run a red wire from the +ve terminal of the battery into a closeby inline fuseholder the wattage of the pump divided by 12 will give you the amperage of the fuse needed, from the inline fuseholder connect to one wire or terminal on the float switch, the other terminal on the float switch then connects to the +ve wire/terminal on the pump, run a wire from the other terminal back to the -ve batt terminal. Needless to say avoid terminal blocks under where you expect there to be water.
 
A quick numpty question ('cos I don't know!) the rating of a fuse........... wossit mean, ie, a 10amp fuse, does it blow at 10.1 or what? Sorry, but I really don't know, dreadful isn't it. /forums/images/graemlins/blush.gif
 
Depends on the type of fuse - as they have different characteristics. For a standard 10A fuse you might find that it is guaranteed to take 15A for at least one hour, but blow within 30 minutes at 20A, and blow within 1sec at 30A
 
Suppose a bit of kit draws 2 Amps, you could, in theory, protect it with a 3 Amp fuse. Any fault in the device (for example a short circuit) would result in a very large current (say 100 Amp), which would only be limited by the current carrying capacity of your wiring. This would heat, and eventually break. Before doing so, it could smoke, or catch fire, taking the rest of the boat with it. Hence the need for a fuse, which will blow easily. It is not necessary, however, to match the fuse exactly to the load, and in the above example even a 10A (or higher fuse) would still provide protection.

Motors are a bit harder - they often have a surge current when started, and the fuse must accommodate this. Also, if the motor stalls, its current will increase, If the fuse capacity is right it will protect the motor from overheating in these circumsances.

In a nutshell, use the smallest fuse you can get away with.

John
 
[ QUOTE ]
run a red wire from the +ve terminal of the battery into a closeby inline fuseholder the wattage of the pump divided by 12 will give you the amperage of the fuse needed, from the inline fuseholder connect to one wire or terminal on the float switch, the other terminal on the float switch then connects to the +ve wire/terminal on the pump, run a wire from the other terminal back to the -ve batt terminal.

[/ QUOTE ]

Excellent reply very clear -well done.

Could you please comment further on the type of connection to use - i see heat shrink plastic tubing for sale in maplin but have never used same. what about standard crimped connections ? Are they suitable in this environment?
 
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