https://academic.oup.com/ptj/article-abstract/46/9/968/46379...
I have heard people say "that can't be right, because a car battery can source 100+ amps and touching those terminals doesn't kill me!" The reason is because you have a high enough impedance that 100mA doesn't flow from a 12V source through your body.
Honestly I kinda hate that saying. It's like "it's not the fall that kills you, it's the sudden decelleration on impact." For most situations people encounter, it's high voltage sources with more than enough power which are dangerous.
Even 50mA will likely kill you, as outlined on the "death graph" as we electricians call it. This is independent of voltage.
https://upload.wikimedia.org/wikipedia/commons/7/7f/IEC_TS_6...
Blue is harmless and imperceptible, green is harmless, yellow is harmful, red is fibrillation.
Edit: This illustrates why 30mA (or less) RCD protection is common (and required) in various jurisdictions, depending on the kind of circuits you're serving.
That shock was certainly quite unpleasant, but despite touching my sweaty skin against live wires, it seems to have been far from fatal.
Surely the dangerous situations are live-to-earth shocks, which could potentially run across your whole body (rather than just a hand or finger, as in my case). But that's why we have RCD/GFCI protection, right? Those will trip with tiny fault currents, certainly much less than 300 mA.
Secondly, aren't "Type B" RCDs required on solar inverters? Those will detect and trip on DC fault currents as low as 30 mA, not 300!
Next time, I suggest using a breaker lockout [0] in conjunction with the local disconnecting means (light switch, which you can also lock out! [1]) to do it safely :)
[0] https://www.walmart.com/ip/MASTER-LOCK-493B-Circuit-Breaker-...
[1] https://www.homedepot.com/p/Ideal-Wall-Switch-Lockout-44-789...
Mike Holt is an excellent instructor on the NEC and has quite a few videos that speak about this topic.
