Striking a domestic power cable with a "kango" or hand tool

[jonesinamillion]

Which is best?

Obvioulsy neither, and we have measures to isolate supply and have conducted risk assesments etc...

My question is, if you were to strike a 230v power supply with say a 110v "kango", and were holding the handle, would the tool / cables / transfromer give a route to earth this minimising the potential injuryt to the user?

If the same person were to strike the same cable with a metal hand tool .e. a bolster chizel, would the operative be the route to earth and therefore a more severe injury, r would the dangers be the same in each scenario?

Your learned thoughts would be appreciated!

Thanks.

 

[telectrix]

much as i'd like to answer your question, i've got a few years' pension to collect before i can callo it even with the taxman, so i'm not prepared to experiment. :lol:

 

[truckster]

My brother being the impatient sod he is took a Kango off a labourer who was exposing a known 11kv cable because he was 'tickling about' The cable unfortunately turned out to be only inches under the pavement and big bruv went straight into it. The army style jumper he was wearing was melted onto his skin and he spent weeks in oxford hospital burns unit. I saw him several weeks later and I could gently pinch his arm and a blister would appear in minutes. The only saving grace was the kango was brand new and the plastic handles were intact. Unfortunately privatisation meant that there was no come back on the DNO as they only give positions and not depth or quality of install so he got burnt in more ways than one!

 

[mechelec]

Sorry to hear what happened to your brother truckster. In reply to the OP the chances of an electric shock from LV or HV cable strike is small due to their concentric construction. HV protection is faster operating than an LV fuse in many installations and as such LV often produces the worst burn injuries. Best to avoid either really.

 

[plugsandsparks]

I would have thought that the best solution is to be insulated from whatever is hitting the cable and preferable as far away as possible. Would be less concerned about other routes to earth and more concerned about proximity to the blast area and holding anything conductive with your hands. So depends, kango more likely to go through without knowing but further away and may be insulated, chisel - less likely to not notice a cable is there but if there is and no gloves are used a shock is highly likely.

 

[jonesinamillion]

Thanks folks!

I forgot to add, the 110v equipment would be powered from a generator thus independant from the domestic system if this has any bearing on the outcome?


As you may be able to tell, I'm not an electrician :teeth_smile:

 

[jonesinamillion]

Thanks folks!

I forgot to add, the 110v equipment would be powered from a generator thus independant from the domestic system if this has any bearing on the outcome?


As you may be able to tell, I'm not an electrician :teeth_smile:

 

[UKMeterman]

Hi,
Go and search You Tube for the term Arc Flash, that will give you an idea of the power that is released when you strike an electricity main.. and no insulated tool will help...

 

[Paul.M]

230V with a double insulated (a box within a box) power tool would isolate you from the current so no shock would be received although higher voltages (11KV for eg as above) would certainly fail as a barrier. Hitting a 230V cable whilst using a 110V drill would fry the drill, just ask the plumber that did just that the other month with his brand new Bosh, I didn't laugh at him much .

With a hand tool or a nail just like a customer that I had the misfortune of meeting (long story), the current would for a brief second flow through your body if you were in contact with earth. If not in contact with earth the current would flow to the shortest path to earth/neutral which would be in the same cable you've just hit and then trip/blow the mcb/fuse. With my customer she hit the cable with a nail but didn't blow the BS3036 fuse, oh no it took out the BS88 80A! Lucky woman.

 

[i=p/u]

rubber boots, so just a tingle in 230v 230 /1000= .23A but cant go past the rubber boots. now if your other hand is touching some metal or your knee or any other part which could be slightly conductive. well your quids in if your insured or maybe your family..

 

[Knobhead]

OK I’m going back years, but if digging was being done on site in an area where cables are known to be it would be “hand digging only”. Working in a quarry ground levels could change quite easily. Compacted spillage and the cable would be deeper, front-end loaders could shave solid rock away.

We never trusted drawings as far as depth was concerned. I’ve found 11KV cables just 3” down, not the 4’ 6” shown on the drawing. OK I didn’t help that over the years roadways would alter, so where a cable was laid 50 years back clear of roads, the roads moved.

 

[Engineer54]

My brother being the impatient sod he is took a Kango off a labourer who was exposing a known 11kv cable because he was 'tickling about' The cable unfortunately turned out to be only inches under the pavement and big bruv went straight into it. The army style jumper he was wearing was melted onto his skin and he spent weeks in oxford hospital burns unit. I saw him several weeks later and I could gently pinch his arm and a blister would appear in minutes. The only saving grace was the kango was brand new and the plastic handles were intact. Unfortunately privatisation meant that there was no come back on the DNO as they only give positions and not depth or quality of install so he got burnt in more ways than one!

I would certainly have got a solicitor on that one, especially as were talking 11KV here. DNO cables must be installed to there quoted depths, which for 11KV was/is as i remember min 0.75m not just a few inches. This is especially so for public footpaths/walkways and other publicly used area's....

I take it no warning tape present and no protective cable tiles either??