[Amps] Direct rectification of AC mains to derive the amp, VDD, supply

[Roger (K8RI)]

On 9/19/2013 3:29 PM, qrv at kd4e.com wrote:
> If you want "sensitive" try the newest breaker technology - mandated in
> many places AFCI.
>

I saw one of those demonstrated.  The rep actually used two fingers to 
short 240 to ground.  He said it's so quick he didn't even feel it.
I'm not quite that trusting, but that's like the elrctronic brake on 
table saws. If the spinning blade touches your finger it will stop so 
quick you won't get cut.  I don't know if those have been made available 
or not.

73,

Roger (K8RI)


> Local contractors say they are so hyper-sensitive they install them for
> inspection then replace them with GFI's.
>
>>> the near electrocution you describe was due to several concurrent
>>> problems: The short circuit due to a poor solder job, lack of a ground
>>
>> I know what contributed to the problem, but much of the technology and
>> wiring was not available.
>>> fault interrupter, and poor grounding of the equipment.
>>>
>>> If there had been a GFI, it would have tripped as soon as the solder
>>
>> This was in the late 60s.  I'd never heard of a GFI back then and don't
>> think they were available.  Thing is, there are still many homes that do
>> not have GFIs.  The only GFIs in this home are those we have installed
>> and when you are working with older wiring you are taking a lot on
>> faith.  Even after tracing out circuits you have no gurantee that there
>> isn't a branch running off somewhere.  Perhaps an infinished project.
>>
>> Nealy all equipment back then had a 3 wire cord, grounding the case to
>> the electrical ground, so the 101B with the 2 wire power cord and no
>> ground was an anomaly to most of us.
>>
>>> blob made a short, as long as the radio was connected to any sort of
>>> ground, even a poor one. And if there was no ground at all, the GFI
>>> would still have tripped, as soon as you touched that radial wire.
>>>
>>> This shows how important GFIs are. For anyone who has no particular
>>> interest in getting electrocuted because of any stupid little failure,
>>> it's imperative to have GFIs on every circuit, even in those countries
>>> where they are not yet mandatory.
>>>
>>> The incident you describe was in the sixties. I don't think GFIs were
>>> around back then. But today they are, and they are quite inexpensive
>>> (the ones I used in my home cost about 12 dollars each, I have 4 of
>>> them). So anyone who wants to prevent such an occurrence, can do so.
>>
>> I replace the first outlet on a circuit with a GFI which protects the
>> entire circuit..."IF" the circuit is properly wired. GFI circuit
>> breakers are also available for panel installation, but those are not
>> cheap.
>>
>> My entire shop is wired that way (GFI outlet first on the circuit)
>> except for the 240 with all the wiring in surface mounted EMT.
>>
>> OTOH I have to admit, that I've had two GFI outlets fail.
>>
>> 73
>>
>> Roger (K8RI)
>
>
>