Surge / Ground / Lightning

w_tom wrote:

Plug-in protector typically uses as
little or less than 1/3rd and never more than 2/3rds of rated joules
during protection.

Depends on the surge that arrives. Like a service panel suppressor, buy
one with adequate ratings.


An effective 'whole house' protector uses 100% of its joules for all
types of surges

Depends on the surge that arrives.


A plug-in protector rated at 330 volts will start conducting at
maybe 200 volts. When a larger surge occurs, it conducts at 900
volts.

Large surges can hit service panels so you might get 900V at the
service. The significant impedance of a branch circuit for surges
greatly limits the current that can reach a plug-in suppressor. Many
sources recommend adding a plug-in suppressor at "sensitive"
electronics to further limit the service panel let-through voltage.


Bud posts that electronics contain internal protection of 600 or 800
volts. Intel ATX specs demand that internal protection exceed 1000
volts.

bud quotes Martzloff who says 600-800V.

Just another reason why 330 or 400 let-through volts is
irrelevant.

As usual, w_ can’t understand Martzloff. Voltage let-through is
important to Martzloff because the lowest values cause suppressors to
conduct on surges that are not damaging to connected equipment, which
shortens the lifetime of the suppressor.


"My surge protector sacrificed itself to save my computer".
Reality. A protector was so grossly undersized that voltage exceeded
900 volts.

In w_'s mind, plug-in suppressors have minuscule ratings, service
panel suppressors have mega ratings. Plug-in suppressors are readily
available with very high ratings for relatively low cost.

And w_ only buys special MOVs that self destruct at 900V. All the others
depend on energy absorbed.

MOV did what no MOV must do - vaporize.

w_ buys also only buys unlabeled Chinese suppressors that do not have
the UL required thermal disconnect.




Still can't find another lunatic that says plug-in suppressors are NOT
effective?

--
bud--

krw wrote:
In article ,
says...
Mike Tomlinson wrote:

Phone wires were clamped to ground before the 1960s?
It was common to earth one leg of the incoming pair to either the house
ground or to its own rod. An earth connection also allowed "party
lines", where two houses could share one physical phone line pair, each
house with its own number. Disadvantage was that both lines could not
be used simultaneously.

http://en.wikipedia.org/wiki/Party_line_(telephony)

I think they used to ring between the red green for one party, yellow
green for the other party, black green, etc.

No, that would defeat the purpose of the party line. The ringers
either had "distinctive ring" (once for Mabel, twice for Maude) or
were frequency tuned.


They did frequency and distinctive rings. But for 2 parties you can ring
red-to-ground for one and green-to-ground for the other. It is in Mike's
Wikipedia link above. My recollection is black was ground and yellow was
sometimes used for a light in the phone (red and green are phone wires).

--
bud--

In article ,
says...
krw wrote:
In article ,
says...
Mike Tomlinson wrote:

Phone wires were clamped to ground before the 1960s?
It was common to earth one leg of the incoming pair to either the house
ground or to its own rod. An earth connection also allowed "party
lines", where two houses could share one physical phone line pair, each
house with its own number. Disadvantage was that both lines could not
be used simultaneously.

http://en.wikipedia.org/wiki/Party_line_(telephony)

I think they used to ring between the red green for one party, yellow
green for the other party, black green, etc.

No, that would defeat the purpose of the party line. The ringers
either had "distinctive ring" (once for Mabel, twice for Maude) or
were frequency tuned.


They did frequency and distinctive rings. But for 2 parties you can ring
red-to-ground for one and green-to-ground for the other. It is in Mike's
Wikipedia link above. My recollection is black was ground and yellow was
sometimes used for a light in the phone (red and green are phone wires).

Princess phones used the yellow green pair for the dial light. A
transformer was hidden somewhere in teh house to supply the power
(IIRC, a standard 24VAC door bell transformer, but it's been a lot
of years).

--
Keith

krw wrote:

Princess phones used the yellow green pair for the dial light. A
transformer was hidden somewhere in teh house to supply the power
(IIRC, a standard 24VAC door bell transformer, but it's been a lot
of years).


The lamp was on yellow & black. Red & Green are the pair to the CO.


--
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prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

In article krw writes:

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In article ,
says...
krw wrote:
In article ,
says...
Mike Tomlinson wrote:

Phone wires were clamped to ground before the 1960s?
It was common to earth one leg of the incoming pair to either the house
ground or to its own rod. An earth connection also allowed "party
lines", where two houses could share one physical phone line pair, each
house with its own number. Disadvantage was that both lines could not
be used simultaneously.

http://en.wikipedia.org/wiki/Party_line_(telephony)

I think they used to ring between the red green for one party, yellow
green for the other party, black green, etc.

No, that would defeat the purpose of the party line. The ringers
either had "distinctive ring" (once for Mabel, twice for Maude) or
were frequency tuned.


They did frequency and distinctive rings. But for 2 parties you can ring
red-to-ground for one and green-to-ground for the other. It is in Mike's
Wikipedia link above. My recollection is black was ground and yellow was
sometimes used for a light in the phone (red and green are phone wires).

Princess phones used the yellow green pair for the dial light. A
transformer was hidden somewhere in teh house to supply the power
(IIRC, a standard 24VAC door bell transformer, but it's been a lot
of years).

6 volts as I recall. I had one of the transformers around ages ago,
it may still be stashed somewhere.

Not sure about the pair, though, since green/red is tip/ring of pair
one, black/yellow is tip/ring of pair two. Putting the transformer between
green and yellow would be putting the light current on the talk pair,
which would be inviting hum on the line.

More modern wiring uses:

colors:
main/stripe
-----------
white/blue green tip 1
blue/white red ring 1

white/orange black tip 2
orange/white yellow ring 2

white/green tip 3
green/white ring 3

white/brown tip 4
brown/white ring 4

( from http://www.ling.upenn.edu/~kurisuto/phone_wiring.html )


Similarly, I would question the reliability of ring on a single line referencing
ground, since party lines tended to be out longer distances -- the ground resistivity
would make it more difficult to get ring current to the phone(s).

I think the differing ring frequency would make more sense, since mechanical
resonance in the ringer provides a reasonable tuning mechanism.


Alan

In article , Alan
writes

Similarly, I would question the reliability of ring on a single line
referencing
ground, since party lines tended to be out longer distances -- the ground
resistivity
would make it more difficult to get ring current to the phone(s).

It did work though. The mechanical bells in older phones in the UK had
a lower impedance (500 ohm coils vs. 2000 ohm coils in newer phones), so
the ringer would draw more current. The ringer was also two bells
either side of a balanced clapper, so it took little to make it ring -
the more current it was able to draw from the line, the louder it rang.

I remember a neighbour with a party line whose phone had problems -
calling her would give a ring tone in the earpiece, but she would claim
that she had never heard the phone ring. Several visits from the GPO
(as was BT) engineers found no fault, the phone always working when they
visited.

Eventually it was discovered that her party line was grounded via the
waste pipe (lead pipe into a cast iron stack disappearing into the
ground) of her cloakroom toilet, which was little used, and in the
summer, when the ground dried out and the water in the toilet pan
evaporated and ran low, the phone lost its earth and failed to ring.
Flushing the toilet restored normal operation to the phone

--
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Mike Tomlinson wrote:

In article , Alan
writes

Similarly, I would question the reliability of ring on a single line
referencing
ground, since party lines tended to be out longer distances -- the ground
resistivity
would make it more difficult to get ring current to the phone(s).

It did work though. The mechanical bells in older phones in the UK had
a lower impedance (500 ohm coils vs. 2000 ohm coils in newer phones), so
the ringer would draw more current. The ringer was also two bells
either side of a balanced clapper, so it took little to make it ring -
the more current it was able to draw from the line, the louder it rang.

I remember a neighbour with a party line whose phone had problems -
calling her would give a ring tone in the earpiece, but she would claim
that she had never heard the phone ring. Several visits from the GPO
(as was BT) engineers found no fault, the phone always working when they
visited.

Eventually it was discovered that her party line was grounded via the
waste pipe (lead pipe into a cast iron stack disappearing into the
ground) of her cloakroom toilet, which was little used, and in the
summer, when the ground dried out and the water in the toilet pan
evaporated and ran low, the phone lost its earth and failed to ring.
Flushing the toilet restored normal operation to the phone


Now THAT was _crappy_ phone service!


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In article ,
says...
krw wrote:

Princess phones used the yellow green pair for the dial light. A
transformer was hidden somewhere in teh house to supply the power
(IIRC, a standard 24VAC door bell transformer, but it's been a lot
of years).


The lamp was on yellow & black. Red & Green are the pair to the CO.

slap! There I was typing, looking at bud-'s post and *STILL* got
the wires crossed. I *shoulda* had a V8.

--
Keith

krw wrote:

In article ,
says...
krw wrote:

Princess phones used the yellow green pair for the dial light. A
transformer was hidden somewhere in teh house to supply the power
(IIRC, a standard 24VAC door bell transformer, but it's been a lot
of years).


The lamp was on yellow & black. Red & Green are the pair to the CO.

slap! There I was typing, looking at bud-'s post and *STILL* got
the wires crossed. I *shoulda* had a V8.


No big deal. Do you remember that wall wart being the first one
recalled for being a fire hazard?


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In article ,
"Michael A. Terrell" wrote:

Do you remember that wall wart being the first one
recalled for being a fire hazard?

That was one of Western Electric's first uses of a third-party supplier.
In this case, it was Ault Manufacturing.

The Ault transformer recall was HUGE.

There are still MANY Western Electric dial-light transformers in service
to this day. Virtually all are powering NOTHING but have not been
unplugged.
--

JR