I2C Lines EZO Non Isolated carrier board

This is with reference to the explaination that I found on mycodo home page where you have explained how it is safe to use 5V on I2C lines if none of the devices have pulled up SDA SCL lines with a resistor, but the Atlas Non Isolated carrier board has SDA SCL lines pulled up to VCC with 4.7K resistor. In our case it is 5V. So is it advisible to use 5V as VCC in this case?

It is never advisable to pull SDA or SCL to 5 volts on a Raspberry Pi unless you want to destroy it.

Hi Kyle,
Wish you a merry Christmas .Thank you for the quick response. I noticed that in your set up you have used an old version of carrier board which do not pull up SDA SCL lines. But the product link of Amazon that you have mentioned on website takes us to this new version which have pull up resistors. So people without much understanding of electronics may buy new version of the board from the link and end up destroying the Pi thinking as if this is the board recommended by you and it is the right choice. Also Atlas scieintific have included New version in PT1000 kit by default which may create problems

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There’s not much I can do other then tell people what they should and shouldn’t do. If they choose to solder in the resistors against my instruction, that’s not my fault.

Hope people will read this before using that board. Thank you

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Resistors are always provided with the boards, but that doesn’t mean you have to use them. It’s ultimately up to the person assembling the board to understand what they’re doing. They can always use other pins for I2C if they damage the default pins. 40 is often more than most people ever use, anyway. Merry Christmas.

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