Toshiba 42H81 Blows Fuse at Random

Maybe you have the wrong fuse in there?

Most likely requires a slow blow type..

Well the chance of this unfortunately is not good. Maybe you should think more along the lines of making the part fail. I've at least once in my 30 some years in the industry over fused an intermittent and then looked for smoke/fire. I'm not outright suggesting you do so but it is a last ditch consideration.

I've come across equipment before that has the wrong fuse specified. For various reasons the manufacturer uprated it later on. And of course, the manufacturer might not be in a hurry to point out its mistake .......

Gareth.

Naught, naughty. That alone is a CE / IEC fail.

Graham

What circuits does this supply line service? Monitor each circuit to see how much each is drawing. Fuse each circuit supplied by this fuse individually if the excessive current is intermittent. When that circuit blows its fuse you know where the problem is.

Leonard

You could temporarily substitute an AC ammeter for the fuse and watch the current. Alternatively, you could use a large fusible resistor, say 1 ohm at

Mark Z.

That's basically what I plan to do. I have a Fluke DMM that can record min/max readings, I plan to insert it at various points in the circuit and have it record any current spikes when and if they occur. Hopefully it should help narrow the problem down.