On 12/04/2018 13:05, Theo wrote:
newshound wrote:
For reasons I won't bore you with, I'm interested in building a cheap,
simple data logger to monitor mains voltage, ideally two channels (live
to earth and neutral to earth). In the dim and distant past I have
designed and built such things more or less from scratch, but surely
someone has already done this.

What do you want to do with the data when you've measured it?

Theo

I'm trying to see if there are overvoltage transients on a farm site,
and/or what the neutral is doing. Slow, rather than fast transients. I
recognise that the arduino analogue inputs are multiplexed.

So, I want to collect data for a week or so, then pop it into Excel to
see if anything is going on.

Would you go for Arduino rather than adding an ADC to a Pi?