Most amps i have seen use the 3rd wire as a neutral.....If you have anything at
all for power, you are gonna ground it anyways.
the thread concerning the man who added the centurion that all of a sudden had
RF problems is not an uncommon one.
100 watts is relatively easy do deal with, 1200 watts will show any grounding
weaknesses quickly.
In my opinion, the fuse box does not offer an adequate safety ground, the
farther away from the box you are, the more resistance, and chances of weakness
can present itself.
just an opinion
STEVEN GRANT W4IIV
"R.Measures" <r@somis.org> wrote:
>Rich,
> I'm sorry that I'm going to have to disagree with you on this. You wrote
>(in response to my warning that there
>can be a voltage differential between neutral and ground):
>
>> ** But only if the neutral wire is severed while the radio operator is
>> standing in water without wearing his fishin' boots.
>
> I appreciate the humor, but there have been sufficiently many tragic
>occurrences of the 'electrical equivalent' of this
>situation that there are now specific prohibitions in the NEC and local
>electric codes.
>
** What if the same tragic occurrence that severs the neutral wire also
severs the ground wire? It seems to me that to assure against this
possibility, two ground and two neutral wires are needed to maintain a
high level of safety.
- I just bought a new California Air Resources Board 1-gal gasoline
tank. This tank is quite safe since the lid closes via a spring unless
both hands are pressing on the tank and one hand is also holding the
special funnel. Getting gas out of the tank into the funnel would be
easier with three hands. Not getting gasoline on the hand that holds the
special funnel against the spring loaded spout is a skill not easily
mastered. Nomex gauntlet gloves and a nearby foam fire extinguisher are
clearly in order.
> As another poster pointed out, the neutral carries substantial current,
>and a defective connection with can and will
>cause a differential. As you point out, the peaks current can be much larger
>than the average, and with startups of
>electrical motors (e.g. air conditioners) there is a peak current that could
>generate a substantial differential across
>a relatively small resistance. Some residential systems are old and poor
>connections are not uncommon. Further, in the case of
>fault on the utility side, (I've seen HV transmission lines fall and come in
>contact with the 240 V residential feed), this
>the fault current would be distributed between the path to ground in the
>service entrance and the connections between
>neutral and ground - with disastrous results. In the past, there used to be
>a 'grounding strap' that would bond ground and neutral
>on large household appliances (stoves, driers etc). These are now
>prohibited.
>
> I understand your point that this is an unlikely occurrence, but it can
>and does happen, and it is specifically disallowed in the
>electrical codes. Since there was apparently some confusion in the initial
>posting regarding the practice of attaching
>neutral and ground, I wanted to underscore the importance of this.
>
> But fishing boots are good too. ;-)
>
>Ed
>
>----- Original Message -----
>From: "R. Measures"
>To: "Ed Briggs" ; "Jason Buchanan"
>; "AMPS"
>Sent: Wednesday, December 03, 2003 9:25 AM
>Subject: Re: [Amps] 220V service for amplifier
>
>
>>
>>
>> >Use a NEMA 6-20R and corresponding plug. For 20 amps, you need #12
>> >conductors or larger. I use 3 #10 conductors with a 20 amp circuit
>breaker
>> >on my Centurion.
>>
>> ** For powering a single-phase amplifier with a capacitor-type HV
>> filter, it is better to go with larger gauge wire than the electrical
>> code specifies because I-peak is typically 10x I-average for capacitor
>> filters. As a rule of thumb, for longish runs to big-uns, I use the
>> largest gauge Cu wire that will fit in the receptical terminals.
>> However, for resonant-choke filter supplies, the opposite effect takes
>> place - but on a smaller scale, which is why Henry Radio's old 2k and 3k
>> line of amplifiers are ideal for operation from a 120v outlet.
>> >
>> >The three conductors to the Centurion and to your (receptical) are two
>hot
>> >conductors and ground (not Neutral). The centurion does not use the
>neutral
>> >to develop 120 volts for the fan on a 240 v connection.
>> >If you tie it to the neutral, there is a possibility of a voltage
>> >differentail between the amp chassis and the earth ground which can
>create a
>> >dangerous situation.
>> >
>> ** But only if the neutral wire is severed while the radio operator is
>> standing in water without wearing his fishin' boots.
>>
>> >You should not tie the ground and neutral together anywhere except at the
>> >service entrance. For additional information see the National Electrical
>> >Code and various study guides at a local public library.
>> >
>> >Here is a link where you can see various recepticals, including the NEMA
>> >6-20R.
>> >
>> >http://www.evenheat-kiln.com/technical/recept/recept.htm
>> >
>> >Cheers.
>> >----- Original Message -----
>> >From: "Jason Buchanan"
>> >To:
>> >Sent: Monday, December 01, 2003 10:19 PM
>> >Subject: [Amps] 220V service for amplifier
>> >
>> >
>> >>
>> >> I did some searching through the list but haven't managed to hit the
>> >> nail right on the head yet...
>> >>
>> >> For wiring a Ten-Tec Centurion amp to 220V, are there any recommended
>> >> plugs and outlets to use?
>> >>
>> >> I am thinking about using a 3 or 4 prong clothes dryer outlet and plug
>> >> combination for quick/easy disconnect, however the thing i'm wondering
>> >> about is where the neutral and ground tie together, since i'm fairly
>> >> sure that the Centurion doesn't have a 4 wire power cable running out
>of
>> >> it. Maybe i'm wrong (probably am wrong).
>> >>
>> >>
>> >> Any help and advice how to properly wire the amp would be greatly
>> >> appreciated.
>> >>
>> >>
>> >>
>> >> thanks,
>> >> Jason
>> >>
>> >> _______________________________________________
>> >> Amps mailing list
>> >> Amps@contesting.com
>> >> http://lists.contesting.com/mailman/listinfo/amps
>> >
>> >_______________________________________________
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>> >
>
>
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