[QUOTE=chiques;3497]I know 120V AC is pretty dangerous. Is having 12, 12VDC batteries in series just as dangerous?[/QUOTE]
100ma across the heart will stop it or cause it to go into fibrillation. Your normal skin resistance is 1000 Ohms. If your skin is wet, or you are sweaty, or wearing any metal, or standing on a conductive surface, (concrete/metal ladder), your skin resistance may be far less than that <500ohms. In this situation 50 Volts (AC or DC) may kill you. With DC it can be harder to let go. Over 600 volts can depolarize your cellular membranes causing a delayed death up to 1 day after being shocked. Also causes permanent nerve damage and deep tissue burns. Burns and nerve damage can be caused by lower voltages especially if wearing metal jewelry. Use safety with all electrical power, remember you can’t turn off a battery. Get in the habit of using only one hand, this lessens the chance of current crossing the heart. Break your battery pack into <50 volt strings if possible, (use switches contactors, or removeable fuses). Stand on a rubber mat, (dry). Use electrical rated gloves when working on battery pack. cover all exposed metal on terminals and tool used for attaching cables. Also you can get flash burns from an arc if a battery is accidently short circuited. Be carefull; we are used to the hazards associated with Gasoline, High power electricity is new to some people. Both can be dangerous if careless. We know don’t smoke around gas, use ventilation for flammable vapors and carbon monoxde. Keep sources of sparks far away, keep fire extinguisher handly. Electricity has its own hazards also, and proceedures and precautions to use safely. There are numerous sources of electrical safety get familiar with them. Read up on white zombies plasma incident. Coat terminal bars with a non conductive coating wherever you can to minimize the chance of this happening to you.