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Thermal fuse vs normal fuse

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Vizier87

Active Member
Hi guys,

I was trying to replace a thermal fuse from my rice cooker and it seems that it has a 250V/10A label on it. I haven't been able to get a similar one nearby which means I'd have to order it online or travel to an electronics bazaar in the capital and boy I hate the traffic over there. I wonder if normal fuse with similar ratings would work as well?

Thanks.
Vizier87
 

alec_t

Well-Known Member
Most Helpful Member
I wonder if normal fuse with similar ratings would work as well?
No, it won't. A thermal fuse is designed to trip above a certain temperature. A normal fuse trips at a certain current overload.
 

dr pepper

Well-Known Member
Most Helpful Member
Ditto.
Though the thermal fuse may have give current and temp protection.
 

Vizier87

Active Member
I see. Thanks. I did a bit of wiki:

Unlike electrical fuses or circuit breakers, thermal fuses only react to excessive temperature and not to excessive current (unless the excessive current is sufficient to cause the thermal fuse itself to heat up to the trigger temperature).
So it reacts to the ambient heating, not from resistive, is it?
 

dr pepper

Well-Known Member
Most Helpful Member
Maybe both, ambient melts the internal wax (if thats the topology) and a little spring seperates the contacts, or excessive current flow heats the fuse (via resistance) and that does the same thing but self heats.
 

Vizier87

Active Member
Hi guys. A little update here. I have replaced the fuse with a higher rating and it still trips. The rice cooked well though. I suspect it tripped during the warming period.

Any other suggestions on the repair? Or should I just scrap it already?
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Hi guys. A little update here. I have replaced the fuse with a higher rating and it still trips. The rice cooked well though. I suspect it tripped during the warming period.

Any other suggestions on the repair? Or should I just scrap it already?
Assuming you replaced it with the correct thermal fuse, then it's getting too hot, causing it to blow - presumably the thermostat is faulty?.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Hi Uncle Nigel, thanks for your reply.

How do I check whether it is faulty? Are there terminals which need to have certain ohmic values between them?
No idea, I've never seen one :D

However, the thermal fuse blows if it gets too hot, so if it blows the correct replacement fuse then it's getting to hot.

But you're not going to be able to check the correct temperature by static tests, only while it's working.
 

dr pepper

Well-Known Member
Most Helpful Member
I'm going to bore you now, changing the fuse for a higher temp isnt really safe.
Sounds like one of the elements has shorted or the 'stat isnt working.
 

dr pepper

Well-Known Member
Most Helpful Member
Rest in pieces rice cooker.
Dont forget to rob anything useful of it first.
 
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