wrote:
Okay, I fail to understand.

Formerly, the 2-wire cord was connected to pins 2 and 4 of the Yaesu
connector. These I assume correspond to the +hot and -hot of the 120V
input winding to the step up transformer, leaving the ground floating.
I looked at my 3-wire cord and determined that my hot wires were the
black and white ones for the 3-wire cord, and that neutral (chassis
ground) was green. So I connected wall ground through ground line of
the cord to chassis ground pin of the plug, leaving the hot connections
unchanged.

Is there something I should be doing different?

Thanks,

The Eternal Squire

Hi Squire,

The black wire is called Line, or we can call it hot+
The white wire is called neutral, or we can call it hot-
The green wire is the safety ground, and it goes to pretty
much any screw on a permanent part of the metal chassis.
(eg. don't use a cover screw, if you can avoid it.)

Technically, the green wire is supposed to have a crimped on
lug that is a closed circle, rather than a fork. This is
so that if the screw loosens, it won't fall off right away.

If the FT101 doesn't have markings for line and neutral, it is
usually a good idea to make sure that the line (black) goes to
the fuse. If Yuasu did things correctly, the other side of the
fuse should go to a switch, or relay contact.

[Note, if the fuse is one of the type with a screw in, or
bayonetted cap, the side of the fuse that goes closest to the
power line should be the hidden center pin. This prevents
you from getting zapped when you change the fuse. I have seen
a lot of manufacturers get this wrong.]

-Chuck

"Ron" wrote in message ...
OK that is one case where your need two failures to cause a hot chassis.


NEVER NEVER NEVER connect safety ground and neutral together on an
exposed metal chassis, PERIOD! NEVER.

What if some duffus uses a hardware store cheater on the radio, because he
house ONLY has the older two slot wall sockets? 50/50 shot that the chassis
and cabinet are hot with 120 VAC!!!

The white neutral and black hot should go to the load, the green safety
ground
goes to the metal cabinet. Also, tieing the neutral and hot together
defeats
GFIs.

Pete

wrote in message
...
I believe the important thing here is that a three wire plug be used and
that it gets wired correctly. I will never see why the neutral which is
grounded and green wire which is ground cannot be tied together.

That's why you're dangerous. Sorry. Lot's of people use hardware store
cheaters on safety cords so they can be plugged into older outlets.
You REALLY want an AC hot chassis, or to kill some unsuspecting
future user? Neutral and safety ground ARE NOT the same thing.

Pete

" Uncle Peter" wrote in message
news8Njf.2627$4v.2258@fed1read03...


One final comment, never assume that someone hasn't replaced older outlets
with modern safety ground devices where no safety ground was available in
the
older two conductor cables! A second fatal assumption would be that the
same outlet wasn't wired with the hot and neutral reversed. That's another
reason
why the neutral and ground aren't tied together at the load.

Pete

wrote in message
oups.com...
This is indeed the case for the FT-101E whose schematic I just
examined. What I did was remove the 2-wire cord, and then connect a
3-wire cord where plus and minus hot were in former locations, then
soldered the neutral wire of the cord to the plug's ground pin. Hope
that would work.

Well keep wiring items like this and we may need to send flowers. Do you
really understand what you are doing here? Sounds like you need an elmer -
berfore you kill yourself.

gb

Hi Chuck,

I'm sorry I caused such a panic with my 'alien' terminology. In my
physics class 'neutral' was the name of the wire in a circuit whose
potential was midway between the peaks of an AC signal.

In any case I had wired it as you said now that I understand standard
terms and you understand alien terms

Thanks,

The Eternal Squire

Ron wrote:

OK that is one case where your need two failures to cause a hot chassis.
Now for Doofus to get electrocuted he will also have to have one
hand on this deaf radio and one hand on the radio that has a metal
chassis that is plugged into a socket with a good ground. The problem
you could also have a similar problem even if the neutral was wired
correctly (not tied to ground). If the ground wire broke in the cord or
inside the radio and then a capacitor or a transformer had an internal
short to the chassis or there was a resistor from hot to chassis ground
then the chassis would become hot. The so called safety ground is not a
100% sure thing in the case of a failure. Because safety grounds are as
prone to fail as anything a third external wire tying all metal cabinet
radios together is the only safety measure if one has a table full of
these old AC powered beasts.

Yes it is not a good policy to tie the ground and neutral together. I
just felt that a good explanation of why not to do so was required
instead of just a blanket statement stating "The safety ground must
NEVER be connected to the neutral at the load !NEVER! "

But he on the safe side and ground those boatanchors together. (you can
buy a bigger boat that way).

Thanks
Ron WA0KDS

Ok, Ron here is another possible failure mode: The neutral from the
pole pig goes high resistance or completely open. if both halves of the
240 VAC service are not balanced and the imbalance will cause a current
to flow from the neutral wire, to the radio and back to the ground rod.
If that current is very high the cord will smoke or burn. I had to
replace a breaker box a few years ago after the neutral corroded to the
point it exploded. I was outside at three in the morning repairing the
damn thing to cool my bedroom down so i could go to work the next day,
but nothing had the suggested wiring, or I could have lost my home.
Also, you could have trouble collecting from your insurance company
after a fire caused by your own work.

--
?

Michael A. Terrell
Central Florida

Chuck Harris wrote:

The black wire is called Line, or we can call it hot+
The white wire is called neutral, or we can call it hot-
The green wire is the safety ground, and it goes to pretty
much any screw on a permanent part of the metal chassis.
(eg. don't use a cover screw, if you can avoid it.)

Technically, the green wire is supposed to have a crimped on
lug that is a closed circle, rather than a fork. This is
so that if the screw loosens, it won't fall off right away.

If the FT101 doesn't have markings for line and neutral, it is
usually a good idea to make sure that the line (black) goes to
the fuse. If Yuasu did things correctly, the other side of the
fuse should go to a switch, or relay contact.

[Note, if the fuse is one of the type with a screw in, or
bayonetted cap, the side of the fuse that goes closest to the
power line should be the hidden center pin. This prevents
you from getting zapped when you change the fuse. I have seen
a lot of manufacturers get this wrong.]

-Chuck


Chuck, I worked as a production test tech at Microdyne on everything
except the Scientific Atlanta telemetry product we subcontracted. A new
employee in assembly mis-wired the round metal power connector and QA
missed it: The white and green wires went to the main power switch, and
the black was connected to the chassis. Another tech ignored the written
test procedure and plugged it in for initial testing to see that it
didn't come on. He leaned over to unplug it with one hand on the
aluminum case and his other hand brushed against the bare metal outlet
box where the radio was plugged in. He got a nasty shock and if it
hadn't caused his muscles to contract violently, he would probably be
dead. After that he never questioned the step that required the power
cord to be checked with an ohm meter BEFORE the radio was plugged in.


--
?

Michael A. Terrell
Central Florida

Michael A. Terrell wrote:


Yes it is not a good policy to tie the ground and neutral together. I
just felt that a good explanation of why not to do so was required
instead of just a blanket statement stating "The safety ground must
NEVER be connected to the neutral at the load !NEVER! "

But he on the safe side and ground those boatanchors together. (you can
buy a bigger boat that way).

Thanks
Ron WA0KDS


Ok, Ron here is another possible failure mode: The neutral from the
pole pig goes high resistance or completely open. if both halves of the
240 VAC service are not balanced and the imbalance will cause a current
to flow from the neutral wire, to the radio and back to the ground rod.
If that current is very high the cord will smoke or burn. I had to
replace a breaker box a few years ago after the neutral corroded to the
point it exploded. I was outside at three in the morning repairing the
damn thing to cool my bedroom down so i could go to work the next day,
but nothing had the suggested wiring, or I could have lost my home.
Also, you could have trouble collecting from your insurance company
after a fire caused by your own work.

Hi Michael,

Yep, that is yet another good example of why you shouldn't break the rules.

I could write all week, and still not cover all of the stupid dangerous things
that have happened with ground failures and grounding errors. The NEC
is the result of 100 years of experience with power distribution, and use.
Their collective authors have seen some of the most bizarre failures, and the
code has been designed to help prevent these types of failures.

It is rather unsettling to have a line cord catch fire in the bedroom
when your wife puts a piece of toast in the toaster oven in the kitchen.

And we haven't even broached the subject of what happens when your antenna
gets hit by lightning, and you have invited the ground currents into your
neutral circuits!

In case anyone thinks that losing the connection to the center tap (neutral)
at the pole pig is an unlikely problem. Bear in mind that virtually all
of these connections are to aluminum wire. The power companies make their
own rules. They don't have to follow NEC, they have their own code.
When they started using aluminum wire exclusively in the '60s,
they didn't think about the corrosion and cold flowing characteristics of
aluminum. The power companies use aluminum exclusively for all of the wiring
on their side because aluminum has the highest conductivity per pound, and per
dollar, of any known material.

After they gained experience with aluminum, and knew all about its problems,
I bet you think they went out, and upgraded all of the older connections,
right? Nope! They left them alone. Power companies are profit driven, they
didn't want to have to explain to their share holders why they would have to
shoulder a billion dollar loss to fix a problem of the power company's making.
So, they only fix the problem when *you* discover it.

-Chuck

Chuck Harris wrote:

Hi Michael,

Yep, that is yet another good example of why you shouldn't break the rules.

I could write all week, and still not cover all of the stupid dangerous things
that have happened with ground failures and grounding errors. The NEC
is the result of 100 years of experience with power distribution, and use.
Their collective authors have seen some of the most bizarre failures, and the
code has been designed to help prevent these types of failures.

It is rather unsettling to have a line cord catch fire in the bedroom
when your wife puts a piece of toast in the toaster oven in the kitchen.

And we haven't even broached the subject of what happens when your antenna
gets hit by lightning, and you have invited the ground currents into your
neutral circuits!

In case anyone thinks that losing the connection to the center tap (neutral)
at the pole pig is an unlikely problem. Bear in mind that virtually all
of these connections are to aluminum wire. The power companies make their
own rules. They don't have to follow NEC, they have their own code.
When they started using aluminum wire exclusively in the '60s,
they didn't think about the corrosion and cold flowing characteristics of
aluminum. The power companies use aluminum exclusively for all of the wiring
on their side because aluminum has the highest conductivity per pound, and per
dollar, of any known material.

After they gained experience with aluminum, and knew all about its problems,
I bet you think they went out, and upgraded all of the older connections,
right? Nope! They left them alone. Power companies are profit driven, they
didn't want to have to explain to their share holders why they would have to
shoulder a billion dollar loss to fix a problem of the power company's making.
So, they only fix the problem when *you* discover it.

-Chuck

After the hurricanes last year her in Florida they finally went through
the whole subdivision and replaced every splice in the secondaries, as
well as the 7200 volt primaries. I found a number of them on the ground
and it was amazing that I even had electricity. Between the corrosion
and the thermal expansion you could pull strands out of the crimps.
After they finished my line voltage went up 10 volts, and is a lot more
stable.
--
?

Michael A. Terrell
Central Florida