Switch panel - fuses or MCBs ?

sarabande

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I need to replace a venerable 4 switch panel where moth and rust have corrupted over many years.

I'm going to take the opportunity to put in a a few more 12v lights and sockets, and go for an 8 switch unit.


Are there any particular advantages in buying a unit with normal or car fuses, or one with small circuit breakers, please ?
 

Topcat47

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Some of the fuses I have on board (the auto blade type mostly) suffer badly from corrosion. I've replaced both the holders and the blades of the most vulnerable ones twice in five years. A friend with 12v breakers doesn't seem to have this problem, although it may be a function of where his distribution box is fitted on board. If I were rewiring, I'd go for the breakers myself.
 

lw395

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No moving parts in a fuse.
Breakers are good for things that might be expected to trip, such as a motor that can be stalled.
But how much can you trust a fiddly electromagnetic device to work after being ignored on a boat for 15 years?

Fuses are also available cheaply in a whole range of values.
 

lw395

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Some of the fuses I have on board (the auto blade type mostly) suffer badly from corrosion. .....

The connections to a blade fuse are functionally hard to tell apart from the blade push-on connectors that connector a lot of breakers.
If you are getting corrosion, it's a problem with the design and maintenance of the panel, rather than the fuses.
Whatever you put in that situation will probably give problems of some sort.

Do you take the fuses out once a year, clean and refit with a bit of contact lube or something?
 

michael_w

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Use fuses FFS! You could go through a whole box of the things trying to find an electrical fault. MCBs every time.
 

TSB240

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MCBs rule oK

Except they don't like being regularly tripped. They will age and will not carry the inrush current that they are capable of when brand new. So if you keep tripping your bow thruster you might want to replace it. The price of them has dived since the Chinese bought the old tools off a European manufacturer and marketed them as Chint.

http://www.chint.co.uk/industry/product.php

Cheap as chints. I am allowed to say that on here?
 
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