How to Calibrate the ML8511 UV Sensor for Accurate Readings?

Using Arduino Sensors
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Hi, I'm working on a project using the ML8511 UV sensor and found this tutorial. Could anyone explain how to calibrate this sensor?

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Calibrate for what wavelength or wavelength range of UV?

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I suspect the best you can do is to use the internal Arduino reference and measure with a good quality multimeter. For actual UV measurement I believe this sensor is accurate enough for most application. To get better you would need access to a very expensive UV standard source. And any small benefit you might gain will be overcome by the in accuracy of the Arduino A/D.

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I'm sorry, I shared the wrong tutorial link in my previous message. Here's the correct one: UV Index Meter with ESP32 & UV Sensor ML8511 (how2electronics.com). I need help with the calibration process for the ML8511 UV sensor

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the wavelength

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For what wavelengths do you need to calibrate it?

For calibration, you'll need either a light source that projects a known amount of energy in a known bandwidth/spectrum in a specific spot and use that as a reference. Or you need to use a light source of known bandwidth/wavelength combined with a calibrated meter that you can use as a reference. Neither of these are easily within reach of an amateur/hobby user.

What is your application? I.e. what are you using the UV sensor for? It's quite rare to require better calibration than what the device offers out of the box. If this is to measure the UV index so you know what factor sunscreen to rub onto your arms, don't bother with any calibration.

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Ya I looking for index UV,
so, am I need to calibrate the in uv intensity?

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This may help
https://scitec.uk.com//scitecinstruments.es/uvphotodiodes/notes/uv_index_measuring.php

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Don't sorry about calibration. Your tool will be mostly a toy that gives a very rough approximation anyway. Just go with your favorite online guide on how to build this project and whatever conversion your library of choice gives.

One of the reasons the results are going to be inaccurate in any case is the spectral sensitivity of the sensor, which is not at all representative for the response/risk of e.g. human skin.

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