A device that is used to detect temperature - the word is a portmanteau of thermometer and resistor. The detection mechanism is the measurement of resistance which changes predictably with temperature.
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1answer
37 views
Replicate thermistor behavior for second sensor
I'm working with an R/C electric motor that has a 10K thermistor sensor built into it, which is connected to a speed control that has basic thermal protection. I would like to build a secondary sensor ...
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4answers
95 views
Can I simulate the temperature response of one thermistor by a different thermistor
This sounds like an automotive question, but its really not.
I have a engine temperature sensor (presumably a thermistor, as it reduces resistance with increasing temperature). I need to mate this to ...
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2answers
94 views
Is is possible to produce a resistance that represents the average of two thermistors?
For example, if I want to connect 2 thermistors to a thermostat in a circuit and then return the average resistance between the two of them to the thermostat's ADC.
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2answers
118 views
What kind of Relay Reacts to Ohms?
I need to connect a relay to my old truck to turn on the "soon to add" electric fans.
The ECM has an engine coolant temperature sensor that uses the output resistance to determine coolant ...
2
votes
4answers
161 views
analog circuit to convert one resistance to another
I plan to have a thermistor attached to a CPU heatsink control the speed of a computer case fan.
For temperatures below 30c (room temp) I want to stop the fan, and for temperatures at or above 60c, I ...
3
votes
1answer
61 views
Selecting an NTC for inrush current limitting
I am building a small triac valve for ON/OFF control of a 300W heater. The current design problem is as follows. When the heater is cold, it's resistance is low(15 Ohm @ 220VAC), and the initial ...
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2answers
273 views
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1answer
97 views
Can I change the input voltage for this temperature-controlled fan circuit:? [duplicate]
Possible Duplicate:
Can this temperature-controlled fan circuit be modified for different input voltage?
For the above temperature-controlled fan control circuit which is originally ...
8
votes
4answers
290 views
How to get A, B and C values for this thermistor?
I wonder if it's possible to extract A, B and C values for TTF-103 thermistor from datasheet. Those values needed to calculate resistance using Steinhart–Hart ...
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3answers
292 views
How to change an LED with a thermistor
I was thinking about buying a thermistor and a RGB LED and thereby be able to change the light of the LED, but I'm confused by the resistances I see on eBay. I see some of 100 ohm, 10k ohm and 100k ...
0
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2answers
141 views
Thermistor measuring
I need to acquire the temperature of a box thanks to a thermistor.
I am wondering how to do that with a really high precision. Here are the caracteristics of the thermistor:
T° ...
1
vote
2answers
136 views
Is there a way to wire a digital display into a thermistor input to read the value of that thermistor?
I have a solar thermal system on my house and that system is run by a differential temperature controller having two thermistors. The controller does not have any kind of readout on it, thus I have no ...
5
votes
5answers
482 views
Is this an RC filter?
I'm trying to understand this temperature sensor circuit I came across on a room Air-Conditioner controller (Want to build one myself).
The sensor is an NTC type thermistor (15k at 25 deg C). What ...
4
votes
1answer
105 views
Determining values of thermistors
I was wondering if anyone could help me identify these thermistors. They were included in a grab bag I recently purchased and I haven't been able to find any information about them.
The numbers on ...
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5answers
2k views
Temperature sensors for an Arduino sous-vide project
I'm creating a PID controller for sous-vide, like this one, and am trying to decide which temperature sensor to get.
Priorities:
Cost: < £25 delivered in the UK
Accuracy: +/- 0.5C
Range: 0 - ...
3
votes
1answer
457 views
Drift and “flipping” in Instrumentation Amplifier reading thermistor
Disclaimer: I only have about 2-3 months of semi-intensive electronics experience.
Note that the chip (to the left of the Arduino, is Analog Digital's AD623 Instrumentation Amplifier) Datasheet ...
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0answers
350 views
Voltage Fluctuations in Arduino-opamp-thermistor circuit [closed]
I'm working on a board that takes measurements of voltage off a thermistor through an Arduino and amplified by an opamp (really an instrumentation amp AD623), also there are two potentiometers. See ...
3
votes
3answers
707 views
Compare resistance to a setpoint and trigger a relay
I want to compare a PTC thermistor to a set point, and trigger a relay if the temperature goes below a set temperature.
In particular, my temperature to turn on the relay should be 33 degrees F (845 ...
0
votes
1answer
397 views
ROV (underwater) temperature sensor design considerations
I'm the 'technician' for a SeaPerch ROV team (since I know the most about electronics) and I need an underwater temperature sensor able to mount on a ROV. Since I don't have much experience with ...
5
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1answer
425 views
Operating Temperature Range question for Inrush Current Limiting Thermistors
I have a friend who has brought me a circuit board from her flat screen TV. She assumed it was bad because the TV no longer turns on and there was off-white stuff leaking out of some of the ...
8
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3answers
1k views
Op Amp circuit not behaving as desired
Found a circuit on the net that should do exactily what I want (control a cooling fan) but it is 'on' all the time. Not sure if there is an error with the schematic or if there is something else I've ...
4
votes
4answers
1k views
Differences between thermistors and thermocouples
As I understand it, both thermistors and thermocouples are temperature sensors. So what are the advantages/disadvantages of using one over the other to measure the temperature?
What are the specific ...
0
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3answers
582 views
NTC temperature help
I just started writing a program that represents the temperature of an NTC TT102 thermistor. First I tried the famous voltage divider, but I soon found that it is not good. So I decided to uses the ...
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4answers
272 views
Alternative to NTC Thermistor
I am designing a system which turns on at 45 degC. I want to place a device in series with my circuit that ideally has infinite resistance below 45 degC and then 0 resistance above 45 degC.
I guess ...
6
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4answers
556 views
Lightning/surge protection for a Arduino monitored thermistor circuit
I am considering whether to replace the commercial differential temperature controller on my solar water heater with a Arduino based controller of my own design. I know just enough to be dangerous ...
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1answer
137 views
Measuring temperature of microcontroller and other large ICs
I'm going to be using a microcontroller and SDRAM IC in an enclosure that could, given some environmental variables that I have no control or knowledge of, get too hot for the devices to work ...
8
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5answers
6k views
How to measure temperature using a NTC thermistor?
I have a TTC103 NTC thermistor. It has zero-power resistance of 10 kΩ at 25°C and B25/50 value of 4050. How do I use it to measure temperature?
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2answers
604 views
How to measure EC, pH, 10k thermistor, DO, and Ion-selective probes
Here are the sensors I am trying to measure and then convert into a 0-5V analog output:
pH (acid or base): my understanding is you can use DC voltage to measure this sensor, just not sure what kind ...
1
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1answer
2k views
Thermistors' colour coding same as the resistors'?
WARNING: 30V was a mistake -- better to keep voltage down 12V as a beginner! I tested it over a very short time. Got the things hot over a long time with much less voltage -- apparently not enough ...
