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.

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Interfacing a differential thermocouple pair with ADC

I have a differential thermocouple pair (two K-type thermocouples connected by a common leg) from which I need to sense very small temperature changes between the two thermocouples. Because one ...
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58 views

temperature loss in a metal surface

A metal cone is heated at certain temperature . say 45 -50 deg C. i placed a thermocouple(k type) over the surface of the metal to measure the heat transferred over the metal surface. The ...
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73 views

Welding Thermocouple to Test Sample

I have a 3mm copper test sample that is going to get heated up, and I would like to know how hot it is actually getting. Previously, we have just held the thermocouple close to the sample, but we are ...
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351 views

The Op-Amps don't work correctly for this circuit [Thermocouple]

I'm trying to connect a thermocouple to an Op-Amp to amplify the output of a thermocouple. this is the circuit: Also for R17 I put a 5k09 resistor instead of 6k8 and for R18, 1k032 and for R19, ...
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2answers
79 views

Analog Sensor of 0 to 10 v connection to BeagleBone Black

I have an analog sensor(Thermocouple) which provides an output voltage range of 0 to 10 volt. I want to connect it with a Beagle Bone Black. BBB accepts 0 to 1.8 volt as analog input. I thought of ...
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1answer
57 views

Thermocouple temperatures change drastically when my whole system is powered vs when just my arduino is powered

I apologize in advance if this should instead go in the Arduino stack exchange, but I feel it should be here. I'm using this thermocouple / amplifier pair with my Arduino Uno. I am trying to make my ...
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1answer
36 views

Type K thermocouple durability in semimolten plastic

I want to measure the temperature of a semi-molten piece of plastic, but for my final application I don't want to have to touch the thermocouple. This means it will more than likely end up in the hot ...
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5answers
667 views

Where is the cold junction on the commercial thermocouples?

According to all textbooks and articles, a thermocouple must have a cold junction somewhere on the middle of it. But none of the commercial products have a middle point or a marked spot for ...
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58 views

Cooling an Insulated Chamber using Thermoelectric Cooler

I have a stainless steel cylinder containing some liquid that has to be cooled downw to 5 C. To achieve this, I'm thinking of making an small insulated box (6" x 6" x 10") with a thermoelectric cooler ...
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2answers
76 views

Convert body heat to light [closed]

What thermoelectric device would I use to power one white LED generated by the body heat of one square centimeter skin on a hand. That is, I wish to power one white LED from the heat generated by one ...
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2answers
289 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 ...
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1answer
121 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 ...
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2answers
669 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 ...
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1k 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) ...
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3answers
599 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 ...
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2answers
125 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 ...
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1answer
220 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 ...
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4answers
269 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 ...
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143 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 ...
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2answers
171 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 ...
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4answers
783 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 ...
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1answer
59 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 ...
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2answers
237 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?
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2answers
2k 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] ...
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1answer
85 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 ...
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1answer
2k 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 ...
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1answer
254 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 ...
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2answers
261 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 ...
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1answer
59 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 ...
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1answer
575 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 ...
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1answer
257 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 ...
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1answer
523 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 ...
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2answers
278 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 ...
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1answer
123 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 ...
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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 ...
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934 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 ...
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1answer
1k 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 ...
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2answers
246 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) ...
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1answer
2k 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 ...
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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 ...
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Why do temperature-voltage curves of all thermocouple types pass through the origin?

Notice that the temperature in the graph is in °C, not even in °K. 0°C is the border between temperatures of water and ice under 1 atm pressure. Why do thermocouples give 0V voltage at a ...
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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 - ...
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2answers
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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 ...
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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 ...
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2answers
8k 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 ...
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1answer
4k 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 ...
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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 ...
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2answers
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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 ...
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1answer
499 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 ...
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345 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 ...