Safety handling High Voltages

[Made_from_aliexpress]

This time, I was thinking about the safety involved in handling high voltages,or to be more precise, greater than the OSHA recommended (24VDC).

I´ve seen lots of packs been made on YouTube ,and almost always, I see no one using voltage protected globes for example. Really I don´t know if that's a thing to consider, almost no report of someone been shocked building a lithium pack, at least on YouTube.

For example, at Electric Unicycles voltages,lets suppose they are between 16s and 20s, suppose a potential risk, considering the conductivity of the skin of a human adult and normal humidity conditions.

What are your experiences?

Thanks and have a nice day.

 

[Tawpie]

With lithium ion battery packs, the safety issue is not so much with the voltage as it is with the batteries themselves. The main thing you must avoid is shorting a battery since this can lead to rapid disassembly with loud report, possibly/usually followed by a difficult to extinguish fire. This applies for a single cell at 2.5-4.2V.

I personally wouldn't let myself get across 100VDC... it might not be an issue but 60VDC is generally regarded as "use caution". I don't wear gloves or anything, but I am very very careful. I worked in an industry that charged (very special) capacitors to 2000VDC and we had a saying: you can either be a good example, or a horrible warning. More than one of us were the latter, and they passed around a certificate attesting to their membership in the horrible warning club. Nobody died though, or was even seriously injured (no ambulance rides) so while 2000VDC isn't "safe", it's not automatic death either. 2000VAC on the other hand, is probably automatic death. Huge burn holes at the very least.

Still, don't get yourself across the battery terminals. Treat it as if it was lethal. Don't let the battery wires flop around. No dangling jewelry. Discharge the caps before you get near anything.

[.....]

I managed to arc weld a metal pic to a charge port. It was REALLY FU**ING COOL too! Melted that sh*t real fast. The cool part was I went temporarily blind. I thought the power had gone out, but then realized I couldnt see the sunlight coming thru the windows either. It kinda muted my hearing for a moment too. It was REALLY loud then really quiet. Yup, fun times. My sight eventually faded back in after about 60 seconds. It was a very peacefull 60 seconds too. It must not have been that much voltage(67v) or amperage, as the cigarette in my ear didnt light itself, and I'm sitting here typing about it. I did blacken my finger for a day, but meh, sissyness. Those voltage lines in Hybrid cars look mighty tempting! I found stick welding to be very similar but more usefull. Tbh, I worry more about stubbing my toes in the morning than I worry about electricity. Get ya some! Less filling, tastes great!

Osha can kiss my a**. You know how you DONT build America or repair items in a timely and efficient manner? Ask osha their opinion. Damn hacks are just there to get in the way and turn us into puss**s. If Osha was in charge, we'd all die old and got NOTHING accomplished. Luckily those clowns are too busy publishing BS articles, while REAL workers can continue to get sh*t done.

Edited October 20, 2021 by ShanesPlanet

[The Brahan Seer]

This is a very interesting paper which might help answer some of your questions: 

Conduction of Electrical Current to and Through the Human Body: A Review

See pdf for details

Electric shock.pdf

[Made_from_aliexpress]

On 10/20/2021 at 12:33 AM, Tawpie said:

With lithium ion battery packs, the safety issue is not so much with the voltage as it is with the batteries themselves. The main thing you must avoid is shorting a battery since this can lead to rapid disassembly with loud report, possibly/usually followed by a difficult to extinguish fire. This applies for a single cell at 2.5-4.2V.

I personally wouldn't let myself get across 100VDC... it might not be an issue but 60VDC is generally regarded as "use caution". I don't wear gloves or anything, but I am very very careful. I worked in an industry that charged (very special) capacitors to 2000VDC and we had a saying: you can either be a good example, or a horrible warning. More than one of us were the latter, and they passed around a certificate attesting to their membership in the horrible warning club. Nobody died though, or was even seriously injured (no ambulance rides) so while 2000VDC isn't "safe", it's not automatic death either. 2000VAC on the other hand, is probably automatic death. Huge burn holes at the very least.

Still, don't get yourself across the battery terminals. Treat it as if it was lethal. Don't let the battery wires flop around. No dangling jewelry. Discharge the caps before you get near anything.

Thanks for your advice

[Made_from_aliexpress]

On 10/20/2021 at 6:53 AM, The Brahan Seer said:

This is a very interesting paper which might help answer some of your questions: 

Conduction of Electrical Current to and Through the Human Body: A Review

See pdf for details

Electric shock.pdf 588.93 kB · 4 downloads

Thank you for sharing this paper, after a quick glimpse I found it really interesting. I´ll read it later in detail.