General Fuse Size Question

Anthony605

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Hi! I built a cabinet that is using just an isolation transformer and a Happ Power Pro power supply. What do you think the proper size fuse is to protect both on one circuit? 1.5 slo-blo fine or higher?

Also, what would the a good size fuse be to protect just a marquee light?

Thanks!
 
Hi! I built a cabinet that is using just an isolation transformer and a Happ Power Pro power supply. What do you think the proper size fuse is to protect both on one circuit? 1.5 slo-blo fine or higher?

Also, what would the a good size fuse be to protect just a marquee light?

Thanks!

People can correct me but I thought most cabinets have a 3a fast blow protecting its main circuit. The Bob explanation below shows how but didn't say the fuse rating. I'm reasonably certain it is fast blow 3a.

http://www.therealbobroberts.net/acwiring.html
 
Wow. This is awful.

Let's Play Reverse Engineering 101.

What is the worst-case load (lowest voltage to maximize current?)

This is usually a very small number. Double it for margin (some vendors lie).

This value is used to size the wire. Round the current up to the next wire size (margin)

Now that you have the size of the wire, what is the right fuse to protect the wire?

That is all fuses do - they keep the smoke in the wires. They do NOT protect the circuit - they blow to protect the wires when there is a fault in the circuit.

This epiphany has been brought to you by me.

We now return you to your regularly scheduled thread.
 
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