My datalogger is for 600VAC maximum, but sometimes my source is higher like 630V or so or maybe higher on malfunction or other problems. I would like to build a resistive divider to reduce the input to the logger by a 2:1 ratio. I can easily adjust the PT ratio in the software by whole numbers.
My thoughts are that if I arrange three 1 watt resistors in a delta configuration and then connect another three from each corner of the delta triangle to L1, L2, L3 then I will be able to read one half the source voltage at the corners of the triangle if,
the resistors in the triangle equal the source lead resistors divided by 1.73.
If this is correct, and I am not entirely sure it is, then if i chose a 1 MEG resister for each source resister, then I will need to select a 578.03 K resister for the triangle ones.
I am going to have to search hard to find combinations of two values to fit this equation so I wanted to check to see if my assumption of values is correct
Any related advice appreciated.
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