what kind of fuse on the defender power panel assembly?

Superully

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what kind of fuse on the defender power panel assembly?

one of the fuses on my defender power panel assembly is blown (see pic, the circled one that's sticking up). the only thing written on the fuse is 250 VOLT on the one side (i live in germany and therefore have a european defender) and BOSS MTH 4 on the other. if i read the schematics correctly is says LINE FUSE 3AMP 115V.

slow-blow/fast-blow?

noob question: do i also have to use a 3AMP fuse for my defender (reminder: 250V)?

thx for your input!
 

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You need a 3 amp fuse, the voltage doesn't matter between 115v and 250v. It is a fast blow fuse.

The weird thing, is that big silver cap that doesn't belong on your power brick.
 
The weird thing, is that big silver cap that doesn't belong on your power brick.

That was the first thing I noticed, too. It took a minute to find the fuse I was so distracted. :confused:

The Defender schematics list it as a 3ASB (slow blow) fuse.

ken
 
You need a 3 amp fuse, the voltage doesn't matter between 115v and 250v. It is a fast blow fuse.

are you sure about the fast-blow fuse? someone else told me the following:

I would say that its 3A/115V for 110V configurations or 1,5A/250V. for 220V configurations....
Volt x Amp = Watt
so if 110V x 3A = 330 W we need to divide the 330W with 220V = 1,5A
slow-blow will be fine.

then "another someone else" suggested 3AMP as you did, but slow-blow :(

unfortunately the fuse is blown that much that you can't judge from its interior what it was!

which one would you try first? and why fast-blow over slow-blow?

The weird thing, is that big silver cap that doesn't belong on your power brick.

i've attached two pics of that "weird thing" and how it is attached to the board. obviously it's a replacement for the big blue elko!
 

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YellowDog is right, it is a 3 amp slo-blo fuse that is required.

A 1.5 amp fuse will NOT work.

Interesting how they used that odd cap, the correct one can be pruchased from Ed at www.greatplainselectronics.com for $5.50.

Because of the startup loading in that big stepdown transformer, a fast blow fuse will blow fast. Experience is a wonderful tutor.

As to the antique capacitor it was probably all the operator had handy. Surprised that nobody cut the old one out if it is bad.

Oh well, I've seen worse hacks. The bundle of four 4700 uF caps in parallel for one.....:D

ken
 
I love the distributed bridge rectifier and the 4 wires looking like theu are going to 3 solder pads. WTF is that???? Oh, and I love the cardboard capacitors too.

I've got one sitting waiting for some love with 4 separate diodes instead of a bridge for BR1. And another one that somebody replaced the molex header for the transistors with a PCB screw mount assembly. Creativity knows no bounds!!! :D

ken
 
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