I acknowledge that the subject line indicates a "how long is a piece of string" style question, but I hope to make it more specific below.
I have a "current transformer" (CT) purchased as part of an Efergy energy monitor unit. It appears to be a split core ferrite that closes around the primary (live) with a large number of turns on the secondary. The secondary has a 2.5mm audio jack attached for sampling. I assume there is a resistor inside the plastic case of the mini-CT to enable a voltage drop across it (facilitating sampling).
No wires have been cut to attach the mini-CT, it is simply coupled to one live wire. The live wire is at 240VAC RMS and carries a current of several tens of amps to a household.
Is it safe to touch all the connectors of the audio jack, with my feet touching the ground and the mini-CT attached around an AC live wire that's currently drawing a current?
Would the advice of the previous sentence change if I reduced the ratio of secondary turns from 1:2000 (I don't know if this is the true number, I'm just guessing) to 1:10 or 1:1?