@JMF: What amp of mine? (Post No. 19 above)
Oh OK, I got it now...
Here daytime summer temperatures of 45 Celsius are normal for weeks on end.
It is almost November, 36 at day and 20 at night temperatures, so no air conditioner for now.
I said A/c thermostat, cut in at heat, cuts out at low.
And also an AC fan is quite reliable, use the biggest size that will fit, use a low cfm (= least sound level) model.
Maybe you can use a BC547 or similar transistor as sensor, and trigger fan through that, some circuits will be available on net.
Oh OK, I got it now...
Here daytime summer temperatures of 45 Celsius are normal for weeks on end.
It is almost November, 36 at day and 20 at night temperatures, so no air conditioner for now.
I said A/c thermostat, cut in at heat, cuts out at low.
And also an AC fan is quite reliable, use the biggest size that will fit, use a low cfm (= least sound level) model.
Maybe you can use a BC547 or similar transistor as sensor, and trigger fan through that, some circuits will be available on net.
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The simple schematic that I previously supplied controls a 120V AC water pump as shown.
But connecting the relay to the +12 volt supply to power a small DC fan is also possible.
The circuit includes a variable temprature range pot, and hysteresis, (150K resistor) which also can be modified to suit.
It can be built on a tiny perf board.
Is anyone familiar with these TO220 temperature sensors? Do they us a bi-metal switch or some kind of silicon relay? With these you can monitor the chassis or a heatsink temp directly. The TO220 form factor would be easier to bolt down than the free monolithic kind I guess.
https://www.aliexpress.us/item/3256...duct.73&gatewayAdapt=glo2usa&_randl_shipto=US
https://www.aliexpress.us/item/3256...duct.73&gatewayAdapt=glo2usa&_randl_shipto=US
Dunno,any datasheet?
Bimetals need empty physical space to move, so not straight potted in plastic, but they may very well be inside a small glass tube which in due turn is surrounded by black Epoxy, why not?
Bimetals need empty physical space to move, so not straight potted in plastic, but they may very well be inside a small glass tube which in due turn is surrounded by black Epoxy, why not?
I don't trust anything sold by that aliexpress site, sorry.
As for thermistors, I have a bunch of, and use these typical types, purchased from long-standing reputable places.
As for thermistors, I have a bunch of, and use these typical types, purchased from long-standing reputable places.
Here's the datasheet:
https://www.fuse-china.com/photo/fuse-china/document/25676/KSD-01F Thermal Protector.pdf
https://www.fuse-china.com/photo/fuse-china/document/25676/KSD-01F Thermal Protector.pdf
I translated it with Google, still no indication if its bi-metal, etc. since it only has two leads I'm assuming it is mechanical in some way.
Airpax/Sensata makes switches in the TO-220 form factor - I used them in industrial power supplies. Mouser and Newark carry them, probably others.
What do you mean? It's already in English.
4.1 on the first page "They are temperature fixed bimetal....."
Thermal relay KSD-01F in TO-220 case review. I too have few hundred of them @60 deg C. I put in series with the mains of guitar, OTL hi-fi amp but take a closer look at the potential safety hazard in the review I would have a second thought if I knew before.
Attachments
Link is in Cyrillic script.
Thermal switch in a plastic housing is a contradiction, what happens when it stays shorted in a fire?
Dangerous.
Use wiseoldtech's circuit, or similar.
Safer.
Thermal switch in a plastic housing is a contradiction, what happens when it stays shorted in a fire?
Dangerous.
Use wiseoldtech's circuit, or similar.
Safer.
I use plastic encased or made switches, fuse holders, IEC connectors, mains plugs, terminal blocks, transformer bobbins, power transistors and Triacs, etc. any day of the week.
Don´t you?
As of other comments, just by sheer chance on Cable TV now they are playing:
Small World.
Don´t you?
As of other comments, just by sheer chance on Cable TV now they are playing:
Small World.
I mold plastics, and am considered a specialist in that field.
So your comment is justified, many specially made plastic parts in use, as say fuse holders etc. as mentioned above.
The problem with this was that it is a thermal cut out, to cut the supply in case of temperature rise.
The contacts are set in plastic, not ceramic, and the plastic is not as resistant to temperature rise as ceramic.
Which is why I said it is dangerous. Not fail safe in catastrophic conditions.
So your comment is justified, many specially made plastic parts in use, as say fuse holders etc. as mentioned above.
The problem with this was that it is a thermal cut out, to cut the supply in case of temperature rise.
The contacts are set in plastic, not ceramic, and the plastic is not as resistant to temperature rise as ceramic.
Which is why I said it is dangerous. Not fail safe in catastrophic conditions.
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Plastic has its uses.
But materials like bakelite or other high strength high temp materials (polymers-phenolic-etc) are much safer around high voltages and reliability is insured.
That lousy to220 "circuit breaker" is crap.
By the way, I have the DVD of that movie - loved it. 😉
All this horses*it about them catching fire... if @Koonw has a bunch of them perhaps he can hit one with a blow torch and see what it does...