On Jul 7, 5:08*pm, "Dave Liquorice"
wrote:
On Tue, 7 Jul 2009 03:30:00 -0700 (PDT), NT wrote:
for remote warning of a popped fuse, leds with appropriate
resistors
accross the fuses? or something more fancy.

I doubt you'd see enough voltage across an open fuse to light a LED. A
suitable comparator driving a LED would be more likely to work

Eh? Assuming some load (only a few mA required) you get the full
battery voltage across an open fuse, it's an infinite resistor!

What ever you put across the fuse has to be current limited so an LED
and suitable series R is fine. When the fuse is good it shorts out
the R and LED so the LED doesn't light.


How do you propose to get full battery voltage across the blown fuse?
Lets take a typical scenario, one fuses pops, all batteries have some
charge in them, so the o/c fuse sees anything from nothing to maybe a
few volts under some circumstances.

Comparators are dead cheap, ones that go the +ve rail on the input
would do this job properly no problem. Simply set them to sense more
than 0.1v difference either polarity across the fuse.


NT