diy solar

diy solar

No smoke unless its coming from my ears (safety warning)

Daddy Tanuki

Solar Wizard
Joined
May 11, 2021
Messages
1,808
so two weeks ago my battery pack zapped me while I was wiring in the last 1s16p bank into my system. 64 CALB cells in a 48 volt setup. As they are not new and repurposed second hand cells load tests show me they have a capacity of 185 (avg) vice the 200 they would have as brand new. that's still over 700 amp hours or 38+ KWh available.

so I was sweating my backside off and hooking up BMS leads when I sat back and my left forearm made contact with the primary positive and negative buss bars. got the zap feeling jerked and my pinky finger and part of my forearm has had pins and needles feeling ever since. figure I did some nerve damage there.

I know, blah blah blah... waiting for all the snide remarks. normally my bussbars are covered with a plexi panel I made but as I was hooking up the latest pack I had removed them to facilitate the install and was not thinking.

now at 55 this just means its easier to give myself a numbie without the need of sitting on my hand for 10 minutes :ROFLMAO::ROFLMAO::ROFLMAO: ... but it could have been truly serious. the big question is will the pins and needles in the pinky finger go away or is it a new reality for me.
 
so two weeks ago my battery pack zapped me while I was wiring in the last 1s16p bank into my system. 64 CALB cells in a 48 volt setup. As they are not new and repurposed second hand cells load tests show me they have a capacity of 185 (avg) vice the 200 they would have as brand new. that's still over 700 amp hours or 38+ KWh available.

so I was sweating my backside off and hooking up BMS leads when I sat back and my left forearm made contact with the primary positive and negative buss bars. got the zap feeling jerked and my pinky finger and part of my forearm has had pins and needles feeling ever since. figure I did some nerve damage there.

I know, blah blah blah... waiting for all the snide remarks. normally my bussbars are covered with a plexi panel I made but as I was hooking up the latest pack I had removed them to facilitate the install and was not thinking.

now at 55 this just means its easier to give myself a numbie without the need of sitting on my hand for 10 minutes :ROFLMAO::ROFLMAO::ROFLMAO: ... but it could have been truly serious. the big question is will the pins and needles in the pinky finger go away or is it a new reality for me.
I have done the exact same thing.

When I was setting up my batteries in the shed before heat pump installed I was sweating profusely and laid my arm across the full bank.

More of a burning sensation than anything but I wouldn’t recommend it.?
 
Last edited:
I have done the exact same thing.

When I was setting up my batteries in the shed before heat pump installed I was sweating profusely and laid my arm across the full bank.

More of a burning sensation that anything but I wouldn’t recommend it.?
yeah it was a bit of a wakeup. I have worked around DC for almost three decades and know better... did not stop me from getting zapped. and the pinky is still tingly...
 
Was anything connected to the batteries? Ie a hybrid inverter/charger?

I wouldn't have expected you would get too much of a shock from 50v. But I haven't tried it so I'm probably wrong.

I got a tingle from mine, but it had ~150v or so on one of the terminals due to the inverter not being earthed properly.
 
Nerves can and do regenerate but it happens very slowly. And I’m speaking as someone who suffers from an autoimmune nerve disease which last year meant I couldn’t even hold a pen and write, and now I’m not perfect, but much better.

I would say @ken morgan don‘t worry too much that what you’re feeling now will become permanent, I would be surprised if that’s the case although I’m not a doctor so cant give you assurances. Don’t be surprised if you’re feeling it for months though.
 
Was anything connected to the batteries? Ie a hybrid inverter/charger?

I wouldn't have expected you would get too much of a shock from 50v. But I haven't tried it so I'm probably wrong.

I got a tingle from mine, but it had ~150v or so on one of the terminals due to the inverter not being earthed properly.
Nope they (MS4448 PAE) were disconnected while I worked on the pack. trust me it was a pretty good zap... I think it was a bit of high current availability, coupled with a shit ton of sweat (salt) and just the right amount of pressure to get a good connection.
 
Nerves can and do regenerate but it happens very slowly. And I’m speaking as someone who suffers from an autoimmune nerve disease which last year meant I couldn’t even hold a pen and write, and now I’m not perfect, but much better.

I would say @ken morgan don‘t worry too much that what you’re feeling now will become permanent, I would be surprised if that’s the case although I’m not a doctor so cant give you assurances. Don’t be surprised if you’re feeling it for months though.

Meh at 55 if they don't come back it makes for a strange jerkoff session. ;)
 
No snide remarks from me. I have shocked, burned, cut, bruised, mangled, torn, irritated, abraded and done just about every form of damage that is possible to my body while trying to accomplish things. It is why that I learned to use safety equipment and practice being safe. Occasionally I still get injured.

Hope your nerves get better.
 
I had neuropathy after chemotherapy. The doctor recommended a complex B vitamin for a few months. That seemed to help. There were two flavors of B that were beneficial to the nerves. I think it was primarily B6, but B12 might have been part of the recommendation. The complex had both so it was easier to use.
 
Back when I was in my 50's I was showing signs of getting progressive nerve damage that at first I ascribe to just getting older. Finally I complained to my Doctor about bad back and painful feet and he ordered a test for B-12 deficient anemia. Not sure why that is not a standard test but somehow it is not. It turned up that my body no longer could adsorb enough B-12 from food and that I would need to take mega doses of B-12 as a daily supplement the rest of my life.

It took 6 months to a year of taking 1000mcg of B-12 and the results have been fantastic ever since.

Funny thing it is a hereditary condition people of Northern European or African ancestry are susceptible to. It is also known as pernicious anemia. Strict vegetarians are also at risk because B-12 only comes from meat.
 
I once managed to cut (but not sever, i suppose) a nerve in my thumb on the inside of a computer case. It tingled for months but eventually returned to normal.

I agree with give it a few months before you assume it's permanent.

I have been "electrocuted" with 12 volts many times due to sweat as a mechanic. I usually tell my students "if you've stuck a 9v battery on your tongue, it's like that but 12 instead of 9" ? But i have only 'felt' my 48v system briefly across the bottom of one forearm (aka the usual location) and it was 'incidental' contact so didn't feel much worse than the 12. Just means i didn't push down hard enough. I'm sure I'll 'feel' it again at some point but I do try to be cautious and will certainly take note of this incident as far as not assuming it to ALWAYS be 'harmless aside from pain'. Maybe most times.. but not all times..
 
I once managed to cut (but not sever, i suppose) a nerve in my thumb on the inside of a computer case. It tingled for months but eventually returned to normal.

I agree with give it a few months before you assume it's permanent.

I have been "electrocuted" with 12 volts many times due to sweat as a mechanic. I usually tell my students "if you've stuck a 9v battery on your tongue, it's like that but 12 instead of 9" ? But i have only 'felt' my 48v system briefly across the bottom of one forearm (aka the usual location) and it was 'incidental' contact so didn't feel much worse than the 12. Just means i didn't push down hard enough. I'm sure I'll 'feel' it again at some point but I do try to be cautious and will certainly take note of this incident as far as not assuming it to ALWAYS be 'harmless aside from pain'. Maybe most times.. but not all times..
yeah as many years as I have played with cars and DC power systems, other than the occasional zap from an old school ignition coil I have never been shocked by a car. in my youth I worked at a custom car shop and built several competition audio system that ran into the thousands of watts with stiffening caps multiple batteries and multiple alternators and never got zapped.

So other than the as you mentioned 9 volt to tongue trick I had never been zapped by DC. I am well aware that it can as there are several systems I service on the navy ships that are high voltage DC and you need to be very cautious around them.

I think its more of a cautionary tale as we all get complacent as "its only 48 volts" (ignoring the fact that it could be as high as 58). more than that I think the bigger issues is the capacity of some of the cells we use, and the ability of the cells to dump power at 1 or 2C.

Will just have to watch and see.
 
glad you're ok!

thanks for bravely sharing this learning opportunity so others may have an extra chance to not repeat it ?

good luck with the rest of the project!

here's hoping that the arm feels back to normal in short order.
 
I have been "electrocuted" with 12 volts many times due to sweat as a mechanic.
Careful using the word "electrocuted' it actually means death by electric shock.

I learnt that while writing up an incident report for a guy who received a decent shock from 180VDC at work.
 
Interesting.. I tend not to take the subject of accidental death lightly at all, ever, but i’ve never heard that before. Every time ive heard the word in use it’s been pretty casual. Thanks for the heads up.
 
Last edited:
Well here are my own "sins" :ROFLMAO:

 
Last edited:
The scars of my hobbies have come from electricity, chemicals, fire, mechanical things, and of course love.

"The scars of your love remind me of us
They keep me thinking that we almost had it all
The scars of your love, they leave me breathless
I can't help feeling
We could have had it all"

 
I'm amazed at these reports of getting shocked by 12 and 48 volts.

I've got a 60v battery and had 3 different people touch it both wet and dry. Two fingers in the same hand to positive and negative. None of them reported anything.
 
Back
Top