How Thermistors Work - The Learning Circuit

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[alisonandterry]

I just started researching thermistors yesterday. How crazy is it that you post this today. I have an offgrid refrigerator that has a fairly large temperature difference between the top part of the fridge and the bottom part. I want to use a thermistor at the bottom and top of the fridge in a circuit that will turn on an internal circulating fan when there is a temperature differential between the 2 sensors. Great explanation video. thx.

[deankay]

As an automotive tech, an ASE Master since 78, many ask me about "Low Fuel Sensors." While changing a defective fuel pump, a number of models had the "LED" low fuel light. While not testing or saving these from the trash, I would guess they use a simple "NTC" thermistor. They are a single wire going to the dash in cars & and newer motorcycles, the can has small holes allowing fuel to enter, but always placed on rigid mounts, a few inches from the bottom of the tank. This leaves you with 3+ gallons I have noticed, to keep to running until the next gas station (Unless in South Dakota). With one wire soldered to the fixture, the other exists the tank to the dash light. Inside the 3/4" can, I have found stainless steel wool pack around the thermistor while the other had aluminum foil wrapped around it loosely, but always the wrapped with a parchment paper for insulation wGas is a liquid obviously, but when low, the thermistor is uncovered allowing a few amps via resistor to let it get warmer. As the thermistor gets warmer, resistance drops and the low fuel LED comes. Many happen fast like a 3/4 circle on/off ramp on interstate. With 25 to 30 mA required to turn on an LED, this seems perfect for the job. Most schematics show the return wire simply going to the dash light while others show "Block Logic" circuitry in the dash. Now retired, I would need to order a few to test in a 12.6-14.8 Vdc circuit. Do you have any thoughts? Thanks!
Job well done!
(No offense: but when teaching during a class of 12, or a seminar up to 100+ techs, owners and instructors who worked at the tech school in 7 states; I would ask them t4, the hotter you get them, the lower their resistance) no offense Megan!
Retire ASE Master Tech

[purrydash]

Needed some information on thermistors for a research paper, and I stumbled across this video. I found everything I need! Thank you

[HenricoNar]

Don't wanna learn anything, i'm just here for Karen !

[safwan]

thanx for this video, but what is doped mean ?

[defensegeneral]

So does it matter what resistance value I use then?

[patrykgilbert]

Great Learning!
It's really hard to find good tutorials or learning's in my native language.
So now I'm gonna stalk your channel :)

[ildarhamrayev]

Nice explanation with this he sense of humour 👍

[mguerramd]

I found two failed components on a power supply for a microscope light. They were marked 5D 11 AN. There was no indication of NTC nor PTC. They were little discs, split apart with dark marks on the PCB. I ordered some 5D 11 NTC components to replace them. Does this seem right?

[ozodxon]

Assalomu aleykum
Siz chiqargan videolarizdi mazza qilib ko'raman kayfiyatimxam ko'tariladiii raxmat judayam yoqimtoysiz 😊
ishlarizga omat❤🎉

[MillManD]

I have an window A/C unit that I need to get the room to 60 degrees but the unit will only allow me to set it to 64. I am trying to control the temp by using and Inkbird temperature controller that turns the A/C unit off and on via the outlet based on the inkbird's sensor. In and effort to get this to work, I have tried relocation the A/C unit's thermistor and insolate it but the results are inconsistent.

Can you tell me if I can provide a set temperature reading on the sensor circuit be removing the thermistor and replacing it with a 9K ohm resistor so that it reads a constant 30C?

[joelsilas]

which thermistor is better 10K or 5K or 2.25K ??

[stevepence]

Karen I have watched your logic vids. The questions I have is if you have very specific and expensive part and obsolete how can one model the part with less expensive parts .the part I need to model has counters, latchs and a multiplexer,

[qzorn]

hi, i am so glad that you are karen about thermistors and that's no joke 😂Oooo-my... a wonderful walk thru video, thanks 🥰🥠☕🐥

[Kneejair]

Thank you. I have to tell an engineer with a masters degree how this works

[mattstroker]

So... Noone uses Kelvin (very application specific, I know) and just about only USA uses non-metric values.

Why go all bonkers in the calculations to be able to plot values in C? Why not use those values as a default?

[alfredkaserekasivanzire]

I sell small ntc 10k for students' experiments. I follow more Karen videos than those of men. Women voice calls men.