We’ve even seen the sensors built into a voltmeter ... We’ve seen various types of non-contact voltage and current sensing over the years. We’ve even seen biological voltmeters lately.

[mircemk] shows how to create a simple non-contact proximity sensor using little more than an Arduino Nano board, and a convenient software library intended to measure the value of capacitors.

Global displacement sensors (non-contact) market was valued at US$ 9,017.18 million in 2022 and is anticipated to witness substantial growth, reaching a valuation of US$ 13,743.53 million by the year ...