Hi, I left my electric blanket on , by mistake, and it has blown it's internal 2amp 76degree C thermal fuse
(whether by temp or amp, I'm not sure...my hunch..and it is only a hunch..is that the wires melted , and cause the current to go over 2amps..
as the controller is a few feet away from the blanket, and would be air cooled ? )


anywho, I'm wondering if I could replace the one pass 76C fuse, (in between the 2 resistors)
with a resettable 45C one... ?
ie this one ...https://uk.rs-online.com/web/p/resettable-thermal-fuses/1769081/


On a side note,...
my car's plug in heated seats manage to cut out before they get too hot... I dunno what they use , as this is on the controller


the blue is BVR 07D 180K
and the yellow K G16 500

Any ideas on using a resettable thermal fuse for the electric blanket?
or how the heated seats cut out to prevent damage (I'm guessing there's something eslewhere in the seat to detect a high temp?

Many Thanks
Liam

 

Just purchase a new one, don't fool around and modify safety circuits.
http://uk.farnell.com/panasonic-electronic-components/eyp2bn099/fuse-thermal-cut-off-2a/dp/1832027

(I'm assuming your in the UK)

 

Just purchase a new one, don't fool around and modify safety circuits.
http://uk.farnell.com/panasonic-electronic-components/eyp2bn099/fuse-thermal-cut-off-2a/dp/1832027

(I'm assuming your in the UK)

yes thanks,
I should clarify..... when the electric blanket overheats,
it takes so much heat and current to blow the thermal fuse (76C 2A ),
the blanket itself is toast... wires have melted internally, and it cannot be fixed.
So, a new one is needed £35 $50. the fuse is obviously set to high, and is for a last stand against fire etc.

I was thinking that, on my new untouched electric blanket, I could put the 45C one in series with the existing one,
so an overheat would trip my fuse, before damaging the balnket etc.
Also, if the old fuse is there in series, if it all wne pear shaped , it would blow, as before, and kill the blanket. .

seems like a cunning plan...
liam

 

If the fuse blew there must have been a reason, i.e. the blanket has a fault which caused excess current to flow. Unless you fix the blanket, (a) the fault remains and makes the blanket UNSAFE and (2) the replacement fuse will blow. Even if the blanket were fault-free, the correct working current might well be enough to raise the fuse temp to 45C and blow it.

 

If the fuse blew there must have been a reason, i.e. the blanket has a fault which caused excess current to flow. Unless you fix the blanket, (a) the fault remains and makes the blanket UNSAFE and (2) the replacement fuse will blow. Even if the blanket were fault-free, the correct working current might well be enough to raise the fuse temp to 45C and blow it.

yes ! this is a brand NEW untouched blanket !
The blanket and controller which blew the fuse has been thrown away.
It blew because it overheated , and the internal thermal fuse is too high, meaning when it eventually blows the blanket is already wrecked,
hence my idea oif having a lot lower resettable cutout fuse.

I'll give it a go and see what happens.. the do 50C, 55C etc all the way up...
it's what temp get's sent back to the controleer...I imagine the blanket would be 10+c higher than that at the fuse
and 55C is ok temp for a blanket. It would turn off, and then after it cooled 10C, turn back on etc

Cheers
Liam