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description: Using EuroTherm PID controller
---

# Annealing with PID

If you are going to do many similar annealing procedures in the low-temperature (LT) heater and you need to keep precisely constant temperature, you might want to use a PID controller to keep track of thermocouple (TC) readings for you.

<figure><img src="https://1019940988-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M4xyQ1EYH71vPc02yXQ%2Fuploads%2FTfjSCb9pRaYSv9OizvCx%2F20250710_125016.png?alt=media&#x26;token=2c646a56-8a62-47c3-b43b-2ca4111567b7" alt="" width="375"><figcaption></figcaption></figure>

## How to make it work:

* Check that the cables of LT heater are connected to EuroTherm and the power supply. Do NOT connect the grounding cable of the TC!

<figure><img src="https://1019940988-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M4xyQ1EYH71vPc02yXQ%2Fuploads%2FvpfQZF1LFDS6e5GjzEFT%2F20250711_143143.png?alt=media&#x26;token=6b354dd6-1945-4b7a-863a-4e27ead6393d" alt="" width="375"><figcaption></figcaption></figure>

* switch on power supply
* switch on output of the power supply

<figure><img src="https://1019940988-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M4xyQ1EYH71vPc02yXQ%2Fuploads%2Fdjo4G0nBE98xczIAhNQ2%2F20250711_143058.jpg?alt=media&#x26;token=7e93a830-ece7-4685-ad33-565b82c811e4" alt="" width="375"><figcaption></figcaption></figure>

* check that EuroTherm is in Auto mode (there should be no text "MAN" on top of the screen). If it _is_ in manual mode, press A/MAN button
* use arrows to adjust the setpoint temperature

After this the controller will try to reach setpoint temperature and keep it.

There is a limit on how much power it can use which is shown as percents of the maximum value. The max current of the power supply is ca. 12 A, 20% corresponds to ca. 2.4A.

If you are going to use low T (let's say below 300C), you might want to put this limit lower, otherwise it can overshoot in the beginning by using too much power. If you need higher T, then set the limit higher, otherwise you may not reach the desired T. In the future we plan to configure the limits to be selected automatically.

## How to change the power limit in percents:

* Press menu button (left) several times until you see **Lp1 | Main**

<figure><img src="https://1019940988-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M4xyQ1EYH71vPc02yXQ%2Fuploads%2F4xbDCk6xVH9j7QF6Qg3u%2F%7B1B9F59C1-2B5F-45A4-8828-2D4CF1EFFC51%7D.png?alt=media&#x26;token=257a0df3-4297-4c87-8130-d836230f965e" alt="" width="208"><figcaption></figcaption></figure>

* Press up/down arrows until you find submenu **PID**

<figure><img src="https://1019940988-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M4xyQ1EYH71vPc02yXQ%2Fuploads%2FwgYukZwMo2dlYou4h9OP%2F%7B27A540D3-90B8-465A-804A-2DEAB7C5741C%7D.png?alt=media&#x26;token=f9002266-9edd-4375-921d-a79ba8422265" alt="" width="152"><figcaption></figcaption></figure>

* Use round arrow button and find in the sub-submenu **OPHi**

<figure><img src="https://1019940988-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M4xyQ1EYH71vPc02yXQ%2Fuploads%2FEljLln13AEBn3r8gmrkF%2F%7BF6994D45-6E99-44E9-A464-88FB4EB1F54C%7D.png?alt=media&#x26;token=d4597d26-900f-4b9d-8246-67cfc333a89a" alt="" width="142"><figcaption></figcaption></figure>

* With up/down arrows set the limit (18% in the photo above)
