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Creative ideas for fuse-blown indicator

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I am trying to come up with something simple and reliable for a fuse blown indicator. For a simple LED indicator I could easily do this, but I have at least 10x fuses to monitor and I would like to provide the LED as well as a single external output for any blown fuses.

Something such as this - but this will cause problems when connecting up multiple outputs and I don't want an optoisolator for each.

I have approx 10 outputs that will run at 24-32vdc.

I looked into this many years back, i cant remember all the details but the best idea i came up with was to use a little isolated dc/dc to get a separate supply, isolated from the main supply, to drive the optos or mcu and provide the monitoring.

Well I think I have found my answer by placing the fuse on the low side of the load - this allows me to use a diode and common ground. However the dissipation at 32v is still going to be higher than I would like for a simple indicator so I might have to look into some kind of driver.  ???

You start from the wrong design principle - to light the LED when the fuse fails. The right principle would be to turn off the LED when the fuse fails. The later also covers the case when not the fuse but the LED fails.

The circuit also become almost trivia when you use "LED off" to indicates failure.


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