A thermocouple is formed by a contact of two (2) dissimilar conductors. The voltage across thermocouple is governed by Seebeck effect. Thermocouples are widely used as temperature sensors.

learn more… | top users | synonyms

0
votes
2answers
259 views

Can electronic components work without power?

Can electronic components work without power,with the help of temperature? according to my knowledge,I don't think so,until heat will generate some energy and that will drive component. I have to make ...
3
votes
1answer
74 views

Noisy ADC readings

So I am struggling with a problem, i am sure someone would have faced. I have a RAMPS shield with a arduino Mega working as the brain of my printer Temperature readings from the heater thermocouple ...
0
votes
0answers
27 views

NiChrome Coil Heat and Thermocouple Measurement

Preface: My EE skills are lacking. I'm strictly a hobbyist, I'm usually phishing for a means of getting to the material that will most help me realize my goal. I'd like to build a temperature ...
2
votes
2answers
157 views

Can I use a BC547 NPN transistor as a thermometer?

In the article Electronic Thermometers for Brewers Ken Schwartz talks about how to use a 2N4401 to create a diode thermometer: I attempted a similar setup with a BC547 transistor ( BC547 Transistor ...
0
votes
2answers
166 views

Pt100 wires to make Wheatstone Bridge

I'm currently trying to build a circuit on a breadboard that, through a temperature sensor, gives off a voltage which I need to amplify. I'm using a Pt100 sensor with 3 wires (red, blue and yellow) ...
3
votes
3answers
195 views

Replacing the thermocouple for a multimeter?

I bought a no-name but decent multimeter, and it came with a thermocouple. Let's say I broke it in some way. Can I just replace it with any other thermocouple, or is each thermocouple calibrated for ...
0
votes
2answers
71 views

What is this kind of temperature sensor called (Analogue Devices TMP36)?

I am reading about this stuff, and I have found clear definitions of thermocouples and thermistors online, eg on Wikipedia. But then I also found something different, e.g. what they at AdaFruit just ...
3
votes
1answer
91 views

What is this component in series with my water heater's thermocouple?

The other day we had our water heater go out and the issue was diagnosed to a faulty thermocouple. When the repair man removed the faulty thermocouple he noticed the following disk-like component in ...
3
votes
4answers
183 views

Type-K Thermocouple interface problems

I'm trying to interface to a type-K thermocouple with an ATXMEGA128A4U and have been experiencing some difficulty and I'm hoping someone can confirm the process I am using. Details.. 1. TC is ...
0
votes
0answers
77 views

Type K Themocouple and AD595 Callibration

I have been using a K type Thermocouple and an AD595 Board to measure the temperature of a 3D printer hot end. I have been having trouble lately calibrating this thermocouple to report correct ...
1
vote
2answers
89 views

Fast-stabilising skin temperature sensor

We're currently trying to build a portable temperature sensor for the purposes of estimating human core temperature. This is a bit of an engineering problem (more to do with choice of materials than ...
2
votes
4answers
375 views

Thermocouple reading different from Commercial Datalogger when using Arduino

A K-type thermocouple is connected to a thermocouple breakout board that outputs 1.2V to 8.8V that covers the entire -260C - 1380 °C of K-type thermocouple. This output is than divided by ...
1
vote
1answer
45 views

Thermoelectric couple heating on both sides [duplicate]

In college my physics professor showed us a thermoelectric couple powering a fan. He also explained how if you apply a current it cools one side and heats the other side. I have been working on a ...
1
vote
2answers
139 views

Thermocouple amplifier - single-ended vs differential?

When connecting a thermocouple to an amplifier, what are the advantages of the differential versus the single-ended configuration?
3
votes
2answers
636 views

Grounded thermocouple vs “grounded” thermocouple

I'm having problems with documentation and what appears to be conflicting use of the word grounded. The way I understand it, a thermocouple can be [grounded, ungrounded, or unsheathed] ...
1
vote
1answer
70 views

Thermocouple on a grounded stainless steel box

My present project is a ~6kW switching converter in a sealed stainless steel box. The box is grounded well. When I put a thermocouple on the surface of the box, the reading is noisy. Even if I put ...
0
votes
1answer
1k views

Measure 0-10V using Arduino

A thermocouple amplifier outputs a voltage range of 1.2V to 8.8V for the temperature range -260C till 1380C when using a K-type ...
4
votes
1answer
170 views

Amplifying signal from the copper wires of two type T thermocouples

My apologies if this is too localized, but I am really in a bind. I am attempting to amplify the voltage difference (so to be read on an arduino) between two thermocouple's copper wires, as pictured ...
4
votes
2answers
184 views

Salvage data from a reverse connected thermocouple?

My SAE Baja team had a competition this past weekend, and we were using some thermocouples in order to get some temperature data on the drivetrain and engine. They were hooked up right before the ...
1
vote
1answer
58 views

Time Proportional control

I am developing application for Time Proportional Control of thermostat. I know that the output for heater is proportional to an error. For example, if SetPoint is 20 and proportional band is 2, in ...
2
votes
1answer
341 views

PCB mount thermocouple socket

I am designing a product that uses a thermocouple to monitor temperature. I am trying to decide what is the best way for users to attach the thermocouple to the PCB. I have found the connectors that ...
2
votes
1answer
188 views

Operating limit of K-type thermocouple probes

I was looking to purchase a K-type thermocouple and noticed something peculiar. Wikipedia says it can withstand temperatures up to +1350 °C, but Amazon sells some K-type thermocouples that only go up ...
0
votes
1answer
388 views

How to power an LED with a thermocouple

I'm looking for a device that can convert mV to the minimum required to power an LED. I'm thinking of having a thermocouple or thermopile that will be heated by a constant flame. I've talked with ...
3
votes
2answers
243 views

Does suface area affect thermal coupling design?

I am building my own thermal couplings for a experiment I am doing at home. I want to build a very small thermal generator with them. At each contact point does the amount of surface area involved in ...
2
votes
1answer
103 views

Making a K type thermocouple

It has been said that a K type thermocouple is just 2 wires of different types twisted together (basically). If this is so then can such a thermocouple be made with a copper and steel wire twisted ...
2
votes
3answers
2k views

Economical thermocouple amplifier circuit

I'm looking for the most economical circuit that reasonably accurate circuit for amplifying the voltage produced by a thermocouple (so it can be read by an ADC). For the sake of argument, component ...
9
votes
3answers
503 views

Current produced by thermocouples

I can't seem to find an answer to this on Google. Take a K-type thermocouple for example. The voltage produced is around 41uV/K. I'm wondering how this changes when a load is put across it. What ...
4
votes
1answer
866 views

Handling the output of an AD8495

I am building a circuit with two AD8495 thermocouple amplifiers. I chose them because they are simple to get and quite cheap - there's basically no other reason. Now I need to create an interface ...
1
vote
2answers
216 views

Reflow oven AC cable splicing insulation and thermocouple readings

I'm building a reflow oven. I know what I'm doing, I just want to verify my plans to make sure I'm not doing anything stupid before I start. The idea is to have an arduino (powered externally) ...
4
votes
1answer
1k views

Attaching a Type K thermocouple to a breadboard / prototype board

I'm looking to prototype a low-cost thermocouple interface board. It needs to output a voltage, as opposed to using SPI like several of the ICs I have looked at, since it would be fed into a 10-bit ...
5
votes
4answers
735 views

When should one implement cold-junction compensation in thermocouple applications?

Specifically, when using K-type thermocouples, what sort of accuracy expectations demand cold-junction compensation as opposed to simple calibration? Clearly there's no substitute for direct ...
12
votes
3answers
1k views

Why do temperature-voltage curves of all thermocouple types pass from origin?

Notice that the temperature in the graph is in oC, not even in oK. 0oC is the border between temperatures of water and ice under 1 atm pressure. Why do thermocouples give 0V voltage at 0oC ...
6
votes
5answers
4k 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 - ...
6
votes
2answers
1k views

How do I protect analog circuit from relay switching noise?

I'm making a thermocouple based temperature controller. The thermocouple voltage is measured by using cold junction compensation IC LT1025 and precision opamp LT1050. The measurements are read by ...
1
vote
3answers
1k views

Thermocouple to ADC - with negative and positive voltages

I am trying to interface a K type thermocouple to the ADC channel of a Microchip part. I am interested in negative (to -2mV) and Positive ( to + 4mV) voltages but don't know how to feed them into the ...
2
votes
2answers
6k views

How can high temperatures be measured with Arduino uno and type k thermocouple with out maxing out 500 degrees C.?

I need to measure temperatures of around 1000 degrees C using an Arduino Uno (later to be used for PID control), but firstly I need to overcome the challenge of measuring temperatures greater than 500 ...
2
votes
1answer
3k views

Thermocouple array for generating free electrical energy?

Thermocouple is a material (junction between two different metals) which generates potential difference in terms of millivolts, isn't it? Why don't we create a matrix of thermocouples (many ...
5
votes
4answers
8k 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 ...
6
votes
2answers
913 views

Multiplexed Thermocouple Considerations

I have a side-project to read temperatures from 4 thermocouples (K type, around 500F for coffee roaster data logger), and no previous analog experience at these levels. I've identified two possible ...
5
votes
1answer
423 views

Serial data transfer from Omega DP80 legacy hardware to computer

Can anyone provide me with some guidance on setting up a legacy serial connection on an Omega (brand) thermocouple display? I would like to use the serial data interface (Omega DP80-Ser) to reliably ...
1
vote
2answers
306 views

Thermocouple effect on low voltage/current signals in PCB and connectors

As part of my studies, I am designing a measurement setup for measuring leakage current of SMD capacitors in the ranges up to pico Amps. At the moment I am in research periond and later I will have ...
2
votes
3answers
411 views

Thermocouple connection question

Sanity check: I need to measure the junction temperature (or as close as possible) of an SMD LED. Can I solder the tip of a thermocouple to a leg of the part? Assuming there is no ground loop (the ...
6
votes
8answers
4k views

cheap thermocouples. Homemade?

I need to make a bunch of thermocouples but I don't want to spend a ton buying them pre-made. I only need short thermocouples (like 6-8" long) so if i were to buy them it would be wasting a lot of ...
4
votes
1answer
346 views

More Options for Reading Thermocouple Signals

I've tried a few options for reading the signals from thermocouples over the years. The cheapest way (component cost) is likely to be DIY, and a lot of work involving lots of analogue stuff that I'm ...
2
votes
1answer
117 views

Understanding extra thermocouple voltage between computer and machinery

I developed my own circuit board which reads temperature from a thermocouple. This board also plugs into a computer via USB and my software communicates with the firmware on the board. It's fairly ...
7
votes
1answer
765 views

PCB-mount connectors for thermocouples

Has anyone had good/bad experiences with particular PCB-mount thermocouples? I need to design a circuit board with a connector I can plug a standard thermocouple connector into. (and yes, I am aware ...