Having seen the state of some chinese imported cutters and worse still Heat presses I can imagine this could easily be true..........
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Kent
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I don't with electric but if I didn't do anything I should hardly get anything done here
skotl
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Not going to get much argument from me. I know that whatever is being cut is going to be earthed (through the workbench, rather than the cutter's return lead) and I don't touch the business end of any tool when it's running, whether it's a plasma cutter, welder, drill or angle grinder.
Treat it as potentially lethal and you can't go far wrong.
BUT........if you use a plasma table and that is earthed via the main earth clip this would mean anyone touching it could/will get 240VDC reducing to 120 when its cutting. Assuming I read it right.
norlander
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Thats what I was thinking-my plasma is a drag tip so I actually touch the tip onto the workpiece-but I always wear gloves so I am still alive (I think).
dan.taylor.1
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I wouldn't earth a metal bench with the mains earth as if you have an earth/live fault it could become live with 240v mains! As above don't touch the business end of a tool with it plugged in.
I do feel manufacturers should have made return and earth very specifically different as it causes a lot of confusion re welders etc.
I do feel manufacturers should have made return and earth very specifically different as it causes a lot of confusion re welders etc.
perhaps I wrote it wrong....I meant if you clip to the plasma table instead of the item . "Using the plasma earth clip"
dan.taylor.1
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Ah that's perfectly normal, though maybe not as ideal as with a welder or so I read in my hypertherm manual.
visor_down
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The AWD release that tecarc refer to maybe this
http://www.maintenanceonline.co.uk/article.asp?id=4744
At first glance a lot of plasmas including the 'remanufactured' rebadged ones would appear to have this problem. Interesting that later models appear to have remedied this with a different torch connection.
This particular issue isn't of great concern to me as you have to in theory pull the trigger and touch the torch lead / machine connection.
what concerned me was the work piece being 'live'as is raised above. The fact you never touch the business end would appear to have no bearing on this if I understand correctly and as ukracer summarises above
http://www.maintenanceonline.co.uk/article.asp?id=4744
At first glance a lot of plasmas including the 'remanufactured' rebadged ones would appear to have this problem. Interesting that later models appear to have remedied this with a different torch connection.
This particular issue isn't of great concern to me as you have to in theory pull the trigger and touch the torch lead / machine connection.
what concerned me was the work piece being 'live'as is raised above. The fact you never touch the business end would appear to have no bearing on this if I understand correctly and as ukracer summarises above
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skotl
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My point about the workpiece being earthed wasn't that it would be specifically earthed but that it would be de-facto earthed in that the piece is on a metal bench and the bench is sitting on the concrete floor which is, to all extent, at a very similar potential to electrical earth.
So if there was a problem with the cutter and you were leaning on the workpiece then you're pretty much assured that the route to ground (and to trip an RCD) is going to prefer travelling through the workbench, rather than your body.
So if there was a problem with the cutter and you were leaning on the workpiece then you're pretty much assured that the route to ground (and to trip an RCD) is going to prefer travelling through the workbench, rather than your body.
norlander
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my cut 50 came with a slip on insulating cover for the torch connection at the machine.
If you are on the secondary side of a transformer then it will not trip an RCD. An RCD works by comparing the current flowing through the live and the neutral connection as presented to the RCD hence the earth is bonded to the Neutral before the RCD, if you have a transformer in the way then whilst you may be getting an electric shock from the secondary side, the RCD will still see a balanced load from the primary and hence not trip.
