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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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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52 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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508 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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101 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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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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54 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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116 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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136 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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294 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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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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77 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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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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282 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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581 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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173 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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892 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 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 ...
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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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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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958 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 ...
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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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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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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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340 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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269 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 ...
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328 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 ...
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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 ...
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308 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 ...
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111 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 ...
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692 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 ...