11-02-2015, 11:55 AM
What are doing is creating your own mains supply, completely floating wrt what comes into your house. You are using a double-wound TX to do so.
Exactly: that's the whole idea. And a balanced 120-v. - 0v. - 120-v. supply too, fed from an RCD with suitable fuses fitted also.
You are also separating your local bench "earth" from mains earth and any extraneous earth such as water pipes. Hence under fault conditions . . . .
"fault conditions": such as ?
. . . . dangerous potentials can exist between your "earth" and any other earthed metalwork. If you can guarantee your workshop to be an earth free zone this is a recognised way of working under certain specialised conditions. Otherwise it's dangerous.
As you have said earlier, there are many ways to hurt yourself by misuse of electricity - especially A. C. mains potential. It's all a question of balance and assessed risk. People such as you and I - who have the necessary experience and knowledge - are quite capable of making such a risk assessment - and acting accordingly.
Judging by previous threads in various forums there is widespread misunderstanding about how to create a safe working environment. Much of this misunderstanding concerns isolating TXs but (if you'll pardon the pun) it cannot really be considered in isolation from other aspects of safe working.
O.K., point taken. Although I raised this thread with its chosen name, I was (and am) aware of the answer that that question asked. Call me a devil's advocate if you like, but electrical safety is important and it affects us all. I just wanted to produce a meaningful conversation amongst members on this topic of 'isolation transformers' (for the very reasons you have mentioned above) and then to lead on to my specialised method of using one.
Al.
Exactly: that's the whole idea. And a balanced 120-v. - 0v. - 120-v. supply too, fed from an RCD with suitable fuses fitted also.
You are also separating your local bench "earth" from mains earth and any extraneous earth such as water pipes. Hence under fault conditions . . . .
"fault conditions": such as ?
. . . . dangerous potentials can exist between your "earth" and any other earthed metalwork. If you can guarantee your workshop to be an earth free zone this is a recognised way of working under certain specialised conditions. Otherwise it's dangerous.
As you have said earlier, there are many ways to hurt yourself by misuse of electricity - especially A. C. mains potential. It's all a question of balance and assessed risk. People such as you and I - who have the necessary experience and knowledge - are quite capable of making such a risk assessment - and acting accordingly.
Judging by previous threads in various forums there is widespread misunderstanding about how to create a safe working environment. Much of this misunderstanding concerns isolating TXs but (if you'll pardon the pun) it cannot really be considered in isolation from other aspects of safe working.
O.K., point taken. Although I raised this thread with its chosen name, I was (and am) aware of the answer that that question asked. Call me a devil's advocate if you like, but electrical safety is important and it affects us all. I just wanted to produce a meaningful conversation amongst members on this topic of 'isolation transformers' (for the very reasons you have mentioned above) and then to lead on to my specialised method of using one.
Al.
