can i get killed by high voltage test set up

[khatus]

Hello guys This is High voltage(AC. freq= 50hz) test set up for testing ground insulation of Main pole and interpole coil of traction motors (dc series motor).The leakage current is set to 300mA (max).That is if any ground insulation fault is detected, this device allows max 200mA to pass before it's trips(probably Current sensing relay is used ).my question is Can i get killed by high voltage(as high as up to 8kV)??
because if current is 200mA and voltage is 8KV, The power transferred to my body is (0.2 * 8000 = 1600 watt)

[Buriedcode]

Your calculation is wrong as it won't transfer all "power" to you, as your body has resistance so will limit the current.   Short answer is: yes that could kill you, much more readily than mains.

Whilst many oft-quote the rather crude saying "its the volts that jolt and the amps that kill" it is the current that does the work, but the voltage that allows it to flow through a resistance.  SO.. even if your skin has very high resistance, given high enough voltage, enough current can flow to stop your heart.  V= IR.  I = V/R.  If R is fixed, if V goes up, so does I. 

What that lethal current/voltage is, varies greatly on the person and situation.  Skin generally has a high resistances, but this drops considerably when hands are wet, sweaty (which contains a lot of salt) or clammy. The actual resistance from hand to hand, through the body, not including skin can be quite low indeed.  8kV @ 150mA could kill you several times over, but I have no doubt it one was to run horrible experiments, some would survive, some would die.  Also note if it is particularly humid 10kV can jump a fair way, at least 10mm (I believe its more like 5mm in dry air).

So yeah, take precautions.

[khatus]

I have found this chart from a youtube channel named RimstarOrg

https://youtu.be/9iKD7vuq-rY

[BravoV]

Can i get killed by high voltage(as high as up to 8kV)??

because if current is 200mA and voltage is 8KV,

Yes.

You don't need more complex words answer than my above word.

[joeqsmith]

The Electrical Safety DOE handbook is available free on-line.  This may be a good read. 

[barry14]

The previous answers have covered the dangers of this setup from an electrical point of view.  I would like to point out that the mains on/off switch seems to violate normal practice which is to have a toggle switch flip up to turn on and flip down to turn off.  In an emergency, it would seem that someone might delay in turning off the power since the natural action would be to try to flip the switch down to remove power.

[GeoffreyF]

Yeah  - Duh,  You bet.

Voltages in the KV range also can form plasma arcs, break down the natural resistance of skin and some types of insulators.    I will also say the knowledge  you need to be safe with this kind of equipment is more than you can acquire by reading books or google pages.    You should have some sort of practical experience with someone who has it.

Finally, this type of equipment can store lethal charges in capacitors, which can last for a long period.  If you don't know how to make the equipment safe, don't even attempt to take it apart.

[vk6zgo]

The previous answers have covered the dangers of this setup from an electrical point of view.  I would like to point out that the mains on/off switch seems to violate normal practice which is to have a toggle switch flip up to turn on and flip down to turn off.  In an emergency, it would seem that someone might delay in turning off th power since the natural action would be to try to flip the switch down to remove power.

Not in countries where the domestic switches all work the other way round.
Just about everyone knows that circuit breakers work "up is on", but toggle switches are much more likely to be treated like domestic ones.

[IanB]

I would like to point out that the mains on/off switch seems to violate normal practice which is to have a toggle switch flip up to turn on and flip down to turn off.  In an emergency, it would seem that someone might delay in turning off the power since the natural action would be to try to flip the switch down to remove power.

This is only normal practice in the USA and American influenced regions. Elsewhere, down is on, up is off. My instinctive reaction to turn a switch off is to sweep it upwards. In America that would be a problem.

[IanB]

This is only normal practice in the USA and American influenced regions. Elsewhere, down is on, up is off. My instinctive reaction to turn a switch off is to sweep it upwards. In America that would be a problem.

I should add that where an emergency off switch is required, it is customary to provide a big red mushroom button that you push for off. This I think is universal.

[fsr]

Yes, that's lethal. Ground fault interrupters trip around 5 to 30 mA. 200 mA thru your body can (and probably will) kill you.

[Brumby]

To the Op:  If you have to ask the question, then, for your own safety, I would advise you to keep well clear of this item when in use.

Working with elevated voltages requires a certain level of understanding to remain safe - and it is rather clear you do not have this.

If high voltage stuff interests you, then I suggest you find a mentor who is competent and willing to sit by your side until you develop the knowledge and skills to work safely on your own.

EVEN THEN - don't work on your own.  Have someone stationed near a kill switch, watching you.  They don't need to be skilled in high voltage - only observant enough to know when to kill the power before the power kills you.

[vk6zgo]

Working with high voltages isn't rocket science.
You wouldn't start your motorbike, get up to highway speeds, then step off without expecting something bad to happen.

The same goes for electrical safety.
If you want to mess around touching wiring, make sure the thing is switched OFF!.
The best way to do this is to switch the power off both on the device, & most importantly at the power source for the device.
If it has a lead & power plug, turn off the power point (if it has a switch) & unplug the lead.

If it is hard wired, identify the main safety switch (or circuit breaker) for the device on the appropriate power distribution panel, turn it off, & tag it, so nobody turns it back on.

Having done that, do your "fiddling", step away from the device & only then restore power, warning everybody in the area of what you are doing.

Obviously, experienced people do work on some activated equipment, but in many cases, the accessible power supplies are not capable of supplying sufficient current (either low voltages, or in some cases, high voltage supplies with quite high internal resistance).

[GeoffreyF]

Working with high voltages isn't rocket science.
You wouldn't start your motorbike, get up to highway speeds, then step off without expecting something bad to happen.

Actually it is high voltage science.  People don't start a motor bike without knowing how to ride one.

It's definitely not existential philosophy such as yours.   You appear to believe that a thousand volts behaves like a hundred.  You never mentioned capacitors in shut off equipment or what an Arc flash is.  Do you know? You didn't say.

[vk6zgo]

Working with high voltages isn't rocket science.
You wouldn't start your motorbike, get up to highway speeds, then step off without expecting something bad to happen.

Actually it is high voltage science.  People don't start a motor bike without knowing how to ride one.

It's definitely not existential philosophy such as yours.   You appear to believe that a thousand volts behaves like a hundred.  You never mentioned capacitors in shut off equipment or what an Arc flash is.  Do you know? You didn't say.

It also isn't something to run around shrieking in fear about.
A thousand volts  obeys Ohm's Law, just like any other voltage.

Yes, indeed, capacitors in shut off equipment can store a lot of energy------- a very valid point.
I didn't include a warning about that, because the OP was not playing around inside the equipment, which was being used to test other stuff, so I limited my advice to that.

In a career of over forty years working on high powered Broadcast & TV Transmitters, including all the high voltage supplies used in Tube equipment (commonly of the order of 10kV), & the associated 3 phase Mains supply wiring to them, I have never run into a case of Arc Flash.

Yes, it does happen, most often in the the power distribution industry, when people make mistakes, just as motorcycle accidents do, but it does not make basic advice about turning off Mains supplies to equipment invalid.

Actually, people do "start motorbikes without knowing how to ride one".

You can't get dual control motorcycles, so a learner is doing just that, & following the instructions of the person riding alongside them teaching them "to the letter".

If a prospective rider was regaled with all the gruesome details of what could happen in a bike smash, they would never try to learn.

[Brumby]

A thousand volts  obeys Ohm's Law, just like any other voltage.

That statement unnerved me more than anything else written in this thread.


You have been desensitised to the risks by having an extended exposure to such an environment - and you will have learned to approach things appropriately.  The OP has shown no such knowledge and a thousand volts needs far more respect than ten, irrespective of Ohms Law.

If anything, publishing warnings about safety are - even if felt to be excessive by some - is the responsible thing to do, especially when people are asking some fundamental questions that clearly indicate they have next to no knowledge on the subject.

If those warnings are indeed over the top, then let them make that judgement call - hopefully based on understanding and not on the cavalier suggestion of someone who has decades of experience.

JMHO

[IanB]

The device posted at the top of the thread undoubtedly would be used in context in a controlled situation where the operators have been thoroughly trained in how to use it safely and correctly. No untrained person would be allowed near it.

We have to suspect that the OP is not one of those trained people, and that perhaps the device is no longer in the original place where it was designed to be used.

[vk6zgo]

A thousand volts  obeys Ohm's Law, just like any other voltage.

That statement unnerved me more than anything else written in this thread.

It is nonetheless, true!, & if you were "unnerved", I'm glad I don't have to work on high voltage circuitry with you!

You have been desensitised to the risks by having an extended exposure to such an environment - and you will have learned to approach things appropriately.  The OP has shown no such knowledge and a thousand volts needs far more respect than ten, irrespective of Ohms Law.

Looking back, you will find I was answering GeoffreyF, who compared 1000v to 100v.
Nobody mentioned 10v!
Quite a few people have been electrocuted by 125 v------ quite close to his 100v!
Almost certainly, thousands more than were ever electrocuted by 1000v!

In my first posting in this thread, I also pointed out that some high voltage sources had high internal resistance, so could not source enough current to be fatal
By the same token, the US 125v supply has a very low source resistance, can supply a fatal shock

If anything, publishing warnings about safety are - even if felt to be excessive by some - is the responsible thing to do, especially when people are asking some fundamental questions that clearly indicate they have next to no knowledge on the subject.


If those warnings are indeed over the top, then let them make that judgement call - hopefully based on understanding and not on the cavalier suggestion of someone who has decades of experience.

My suggestions were far from "cavalier".
On the contrary, they were reasoned, & gave the OP some useable instructions on how to work safely with any type of Mains supplied high voltage equipment.
OK, I did not make the point about capacitors retaining charge, but the original posting did not refer to opening up the equipment shown.

JMHO

[Brumby]

OK.  Some of my comment seems misdirected because I did not make the connection between what you said and who you said it to...

However:

A thousand volts  obeys Ohm's Law, just like any other voltage.

That statement unnerved me more than anything else written in this thread.

It is nonetheless, true!, & if you were "unnerved", I'm glad I don't have to work on high voltage circuitry with you!

You really need to comprehend what was written.

I was "unnerved" at your statement because it was advice given on a thread where the OP obviously has NO fundamental understanding.  Not for my sake - but for theirs!

This is why I respond as I do in the Beginners section when potentially lethal voltages are being discussed, especially where there are participants that show their lack of knowledge.  You don't have to worry about me - but I would rather a newbie be given excess caution until they learn enough to be able to competently assess the risks and make their own decisions.

[Synthtech]

To the OP - unless you have a very specific and reasonable purpose for that piece of equipment and looking at the physical condition I would treat it like an unpredictable junk yard Rottweiler and assume that it bites. At the very least have it inspected for safety by a competent person before you energise it. It is dangerous enough in good working order, if it has a fault then it’s even more so.

[fsr]

A thousand volts obeys Ohm's Law, just like any other voltage.

And that means that a 1000 volts has 10 times the potential to kill you than a 100. Probably more, as this is AC and the skin acts as a capacitor, bypassing it's normal resistance.
Beginners don't need to risk their lives working with HV circuits.
That kind of equipment has to be used by following safety procedures, which were never mentioned, and likely unknown to Khatus.
Who has even certified that the equipment is in working condition?
If 8 kV get to you, that's it, your life very likely ends there. It's very easy for that kind of voltage to cause enough current thru the body to kill a person.

[Zero999]

Hello guys This is High voltage(AC. freq= 50hz) test set up for testing ground insulation of Main pole and interpole coil of traction motors (dc series motor).The leakage current is set to 300mA (max).That is if any ground insulation fault is detected, this device allows max 200mA to pass before it's trips(probably Current sensing relay is used ).my question is Can i get killed by high voltage(as high as up to 8kV)??
because if current is 200mA and voltage is 8KV, The power transferred to my body is (0.2 * 8000 = 1600 watt)

mod it into a selectable 5mA limit?

That won't provide complete protection, as something could go wrong, passing the full current.