What type of shock is more dangerous

[anishjp]

Hi,

Out of AC and DC, which one is more dangerous (receiving an accidental shock) to human life..?, and Why...:?:

 

[s_cihan_tek]

which one is more dangerous ac or dc

It wouldn't be right to say something like AC is more dangerous than DC or vice versa. Both are dangerous but their effects changes with the voltage level, frequency and of course the device in which they're used.

If the path of the current flow doesn't contain your heart, the current needed to give you ventricular fibrillation is less compared to DC when AC is in question. AC frequency is another factor, a high frequency AC signal would burn you rather than leading to fibrillation and death.
On the other hand, DC is more likely to stop your heart because it won't allow your muscles to move away from whatever that was giving you the shock.

Also generally the risk of electric shock is higher in AC systems if grid connected systems are in question, due to the fact that the power system is earthed and the only thing that should be done to have an electric shock is touching to a single live wire.

Regards.

 

[Externet]

which is dangerous ac or dc

I would say alternating current is more dangerous.

Because 50V DC is 50 V. 50V AC is actually 140 V peak to peak.

 

[a_tek7]

ac vs dc danger

current is important too.250ma can be dangerous.

 

[madicalphy]

dangers of an electric shock from dc

DC volatge with high current source can be more dangrous, even 50v with 20A is a big source.
so i think votage less than 100 but with high current source are dangrous rather high volatge but low current.
what you people say?

 

[xulfee]

dangers of electric shock ac and dc

Ac is more dangerous

 

[sushain]

ac voltage dangers muscle

if the voltage level of both are same then DC is more dangerous than AC. Shocks due to DC are much more fatal due because of its constant supply whereaes AC regularly crosses zero because of its pulsating nature

 

[umery2k75]

dangers with dc voltage

Why don't electric welders get electrocuted that easily? They use very heavy source of current. We don't see cases of electric welder getting electrocuted.
I think they use very low AC voltage and very high current. There must be a factor by which they don't get electrocuted.If I happen to find a welder shop in my way, I would go and ask what's the voltage and current, those guys use for electric welding.

 

[Awarapunshee]

will 48v dc gives shock to human

Actually it is current that creates problem. But there is enough potential required to flow that much amount of current between two points (of a body etc). Thats why some body receieves shocks even at 60V AC some don't, because of the different body resistance. The minimum amount of current that prove fatal would be a question to discuss. I read some where in a book that there is a letgo current which is 0.8mA to 1mA (I do not remember where I read so I cannot confirm this)

 

[Jack// ani]

how many welders are electrocuted

Why don't electric welders get electrocuted that easily? They use very heavy source of current. We don't see cases of electric welder getting electrocuted.
I think they use very low AC voltage and very high current. There must be a factor by which they don't get electrocuted.If I happen to find a welder shop in my way, I would go and ask what's the voltage and current, those guys use for electric welding.

Yes, that's right, those electric arc welding usually operates low voltage ranging from 20-30V, however, current is quite high 20-100Amps which is adjustable as per welding requirements.

You get electrocuted for voltages usually above 50 volts, that very well explains why electric arc welders don't get electrocuted!

However, you can still get fatal shock if wounded/bleeding part of body is exposed to these low voltages :!:

 

[-jps-]

electricity shock to muscles 240vac dc

voltage is not dangerous but the current the flow within a conductor is so dangerous

 

[MickDDnt]

the dangers of ac voltage

There are too many variables to give a straight AC or DC answer. Going back to basics V=I x R. It is usually a Voltage that you will come in contact with that will cause a Current to flow thru your body. The Resistance of your body will determine how much current will flow thru your body. This will depend on many factors - skin resistance, sweat, wet fingers, rubber boots, wet floor etc.

Remember it only takes 6mA through your heart to kill you. That is why many old timers will put their left hand in their pocket when fiddling inside live equipment. The natural reaction is to grab the chassis with your left hand and poke around with your right hand. If you get a shock the current will run up your right hand across your chest (thru your heart) and exit to the chassis via your left hand. Put your hand in your pocket and the current must find another path.

Some say that DC shocks are worse because your muscules cramp up where as AC tends to make them convulse. As a result DC is more likely to make you hang on where as AC is more likely to throw you off. Again that is why old timers tend to touch a potentially live part (for example an electric fence) with the back of the hand so that a shock will cause the hand to be moved away where as if you touch it with the open palm there is more chance of grabing the live item.

Some also say that 110VAC is more dangerous than 240VAC because 240VAC is more likely to kick you off than 110VAC. I suggest that you try to avoid both and AC and DC!!!

Added after 18 minutes:

An electric welder can have an open circuit voltage up to about 100v between the electrode and work terminals. It is not unusal for welders to get a shock - especially when changing rods. Again there are many variables - sweaty body because of the PPE they are wearing, wet gloves, wet conditions etc.

Many welders are now fitted with VRD's - Voltage Reduction Devices to reduce the chance of electric shocks. VRD's sense that the Welder is not welding and limit the open circuit voltage to 20-30 Volts.

Some Welders don't like VRD's as they say that the VRD makes it harder to stike an arc because of the delay caused by the VRD sensing that the Welder is actually welding and allowing full voltage to appear at the terminals.

 

[hkBattousai]

alternating current ac burns from the inside out

Hi,

Out of AC and DC, which one is more dangerous (receiving an accidental shock) to human life..?, and Why...:?:

It is simple.

Design an electrical circuit representing your body, and calculate whether AC or DC dissipates more energy in.

 

[kiprono]

ac dc fibrillation

A DC of at least 30V is enough to kill. Remember dc hits you without a break. AC at least passes through zero!

 

[hkBattousai]

what harms more ac or dc current

A DC of at least 30V is enough to kill. Remember dc hits you without a break. AC at least passes through zero!

Passing through zero may mean a worst case depending on the circuit we talk about.
How much do you know about human body? Maybe there are some kind of body sections which behave capacitive. They will be sensitive to the "passing-zero" regions of the input voltage.

You must know the circuit structure very well in order to talk about which wave form harms more.

 

[Awarapunshee]

ac/dc more fatal

A DC of at least 30V is enough to kill. Remember dc hits you without a break. AC at least passes through zero!

I don't agree. In reality it is not possible. I did not hear that any body die with 30VDC...However 60V or more than that may be a figure. I had work on 48VDC 100A output power supply and I touched both terminal many times. See I am alive.

 

[hkBattousai]

describe ac versus dc current flow

A DC of at least 30V is enough to kill. Remember dc hits you without a break. AC at least passes through zero!

I don't agree. In reality it is not possible. I did not hear that any body die with 30VDC...However 60V or more than that may be a figure. I had work on 48VDC 100A output power supply and I touched both terminal many times. See I am alive.

Once I built a voltage multiplier circuit. Output voltage was about 65VDC. I touched both terminals (while voltmeter was connected and still reading 65VDC) and didn't even feel anything.

 

[Awarapunshee]

which is more fatal ac current vs dc current

hkBattousai.....Yes you are right it all depends on the body and its condition also. But one should be careful with the voltages higher than 60V.

 

[breneer]

dangerous dc or ac?

voltages are dangerous because of the current..

 

[kiprono]

why is ac more dangerous than dc

Ultimately, all depends on the resistance offered by your body to current flow.