network printer

[philo]

I use a Samsung ML-2851ND which is networked (via wired router). I have
four computers connected to it through either ten foot or a 25 ft
lengths of cat5.


I also have a few 50' cables strung down to my workshop in the basement
and generally would have no need to print from there...but recently was
setting up a machine and noticed that I cannot detect the printer if I
use a 50' length of cat5...though the Internet connection itself is just
fine.


Does anyone know why I cannot use a 50' cable for a network printer,
I'd think that length would not be excessive.


BTW: I did try different router ports just in case some of them may
have been flaky .

 

[philo]

50' is not excessive, but I would definitely try a different cable to see
if it makes a difference.

I've tried two thus far...but I might as well buy a new cable and try
again.

 

[philo]

It seems like something else is going on. How about dragging the computer
up to the router and try with your 50' and other, shorter, cables.

Yep I've done that and it connects fine with the shorter cables, this makes
no sense as the internet connection is fine.

 

[Pen]

Yep I've done that and it connects fine with the shorter cables, this makes
no sense as the internet connection is fine.

Since you've tried everything else, have you tried changing the printer cable?

 

[philo]

yes, I have tried two cables thus far

 

[philo]

Does it still not work with the 50' cable when the computer is right
next to the router?

I have no way to do that, the cables were snaked down through the walls etc.


I am going to put this on hold and eventually get a new cable and try again.

 

[Paul]

I have no way to do that, the cables were snaked down through the walls
etc.


I am going to put this on hold and eventually get a new cable and try
again.

Well, it's not a grounding problem, because Ethernet is
transformer isolated. The transformers on each end,
are responsible for removing common mode noise.
As long as the same amount of noise is coupled into each
wire, it all cancels out inside the transformer. The transformers
come in a DIP style package that is relatively small. In some
cases, the transformers are part of the Ethernet connector stack.

Paul

 

[philo]

Well, it's not a grounding problem, because Ethernet is
transformer isolated. The transformers on each end,
are responsible for removing common mode noise.
As long as the same amount of noise is coupled into each
wire, it all cancels out inside the transformer. The transformers
come in a DIP style package that is relatively small. In some
cases, the transformers are part of the Ethernet connector stack.

Paul

I decided to have another look at things again and it turns out that due
to some of the cables being the same color, the cable going down into my
basement workshop was not plugged into the router I thought it was
plugged into...so that was simply a case of me being an idiot.

I am going to have to put tape on both ends of any cables I have that
duplicate a color.


With the second cable...though I have not yet tested this, the problem
might have been simply that I was using a laptop to test it...and it
might have been using the wireless connection.

At least I know now I do not have two cables that "don't work"


sorry for wasting everyone's time

 

[Paul]

sorry for wasting everyone's time

Not really a waste of time.

Continuous affirmation of just how good Ethernet on
those cables is, is a good thing.

I was impressed, in a lab scenario, looking
at the common mode noise levels on the cable, and how
the transformer isolation made mince-meat
of the noise. Compared to how Ethernet (coax based)
used to work, it's a much better scheme. Few
other interfaces are as safe. Only a fiber
optic cable gives more isolation.

The cable can have up to around 2000 volts of
"spurious energy" connected to it. Above 2000
volts, there are some HV caps that arc over.
Which is why, even with it's burly characteristics,
lightning can still take it out. The lightning
leaps right through the protections, like they
weren't there.

Paul

 

[philo]

O

Thanks for posting a wrap up instead of just slinking off in shame.

Scott Adams points out (rightly I think) that there are two kinds of
people:

1) idiots

2) people who don't know they're idiots

That's for sure. I was considering just "slinking off in shame"
but realized I have gotten in much less trouble by admitting errors
rather than my denying them!

 

[philo]

Not really a waste of time.

Continuous affirmation of just how good Ethernet on
those cables is, is a good thing.

I was impressed, in a lab scenario, looking
at the common mode noise levels on the cable, and how
the transformer isolation made mince-meat
of the noise. Compared to how Ethernet (coax based)
used to work, it's a much better scheme. Few
other interfaces are as safe. Only a fiber
optic cable gives more isolation.

The cable can have up to around 2000 volts of
"spurious energy" connected to it. Above 2000
volts, there are some HV caps that arc over.
Which is why, even with it's burly characteristics,
lightning can still take it out. The lightning
leaps right through the protections, like they
weren't there.

Paul

It's just as well I delved into this. The place where I do volunteer
work is having some networking issues. The company who sold them the
system is doing a very poor job of addressing the issues and has tried
to pass the blame on the cat5 cables and is hinting that maybe they need
to be replaced.

Since the runs are no more than 100 feet, I am quite sure that has
nothing to do with their problem.


Speaking of lightning. I was home the day a lightning hit the power pole
directly behind my house. One of those situations where there was no
delay between seeing the strike and hearing it.

Yes, it scared the hell our of me and my wife...but the only damage in
the house was that the answering machine was taken out.

 

[Paul]

Speaking of lightning. I was home the day a lightning hit the power pole
directly behind my house. One of those situations where there was no
delay between seeing the strike and hearing it.

Yes, it scared the hell our of me and my wife...but the only damage in
the house was that the answering machine was taken out.

You can get surge protection for phone lines.

It doesn't guarantee it'll stop everything, but it's an option.

(Tripp-lite Isobar family...)

http://ecx.images-amazon.com/images/I/41bW5gNYptL._SL500_AA300_.jpg

The nice thing about the metal box on that one, is the shards
of MOV are contained if they explode

*******

Even though I have some forms of protection, I still disconnect
the phone line, if a bad storm is going through. Wouldn't want
to damage that $70 ADSL modem...

Paul

 

[philo]

You can get surge protection for phone lines.

It doesn't guarantee it'll stop everything, but it's an option.

(Tripp-lite Isobar family...)

http://ecx.images-amazon.com/images/I/41bW5gNYptL._SL500_AA300_.jpg

The nice thing about the metal box on that one, is the shards
of MOV are contained if they explode

*******

Even though I have some forms of protection, I still disconnect
the phone line, if a bad storm is going through. Wouldn't want
to damage that $70 ADSL modem...

Paul

I recently moved to AT&T "U-verse" and now have a gateway router for
phone and Internet, so my answering machine should be well protected.

More than likely I will eventually dump the land-line entirely.

The only cell phone I had was from the company I worked for
and I turned it in when I retired a year ago. I have little use for one
now but my wife is addicted to her iPhone.


One nice thing about working for an industrial battery manufacturer was
that I got my hands on plenty of decommisioned industrial grade UPS's.
Every computer in the house is on one.

 

[John McGaw]

On 09/17/2013 08:01 PM, Paul wrote: snip...

I decided to have another look at things again and it turns out that due to
some of the cables being the same color, the cable going down into my
basement workshop was not plugged into the router I thought it was plugged
into...so that was simply a case of me being an idiot.

I am going to have to put tape on both ends of any cables I have that
duplicate a color.


With the second cable...though I have not yet tested this, the problem
might have been simply that I was using a laptop to test it...and it might
have been using the wireless connection.

At least I know now I do not have two cables that "don't work"


sorry for wasting everyone's time

Marking cables is something we all come to eventually. "I know where that
goes" only goes so far. I have an equipment closet downstairs which as at
least 20 plain white Cat 5E cables running into it and I started out
assuming that I could figure out where every one of them runs by some vague
sort of inductive logic. Now every one of them is marked and permanently
tied down to a patch panel so I won't spend hours trying to figure out why
there is no connectivity in a given room.

 

[philo]

Marking cables is something we all come to eventually. "I know where
that goes" only goes so far. I have an equipment closet downstairs which
as at least 20 plain white Cat 5E cables running into it and I started
out assuming that I could figure out where every one of them runs by
some vague sort of inductive logic. Now every one of them is marked and
permanently tied down to a patch panel so I won't spend hours trying to
figure out why there is no connectivity in a given room.

Mine are "mostly" color coded but I forgot I had two gray ones...
I now have the second one marked at both ends with tape.

 

[Paul]

Mine are "mostly" color coded but I forgot I had two gray ones...
I now have the second one marked at both ends with tape.

The techs at work, had some kind of instrument with an acoustic
output. I presume someone was connecting a stimulus to the other end
somewhere, and the tech in the room I was working, would wave his
"detector" near the punch down blocks, and could then figure out
which wire was which. It meant finding the wire on the first try.

I tried a Google on "cat5 tracer", and found an example here.

http://www.storeinfinity.com/cat5-rj11-rj45-network-cable-tester-tone-tracker-tracer.html

I think our circuits were labeled, but of course labels
can be botched and messed up pretty easily. And having a tracer
to use, worked like a treat.

Paul

 

[John McGaw]

The techs at work, had some kind of instrument with an acoustic
output. I presume someone was connecting a stimulus to the other end
somewhere, and the tech in the room I was working, would wave his
"detector" near the punch down blocks, and could then figure out
which wire was which. It meant finding the wire on the first try.

I tried a Google on "cat5 tracer", and found an example here.

http://www.storeinfinity.com/cat5-rj11-rj45-network-cable-tester-tone-tracker-tracer.html


I think our circuits were labeled, but of course labels
can be botched and messed up pretty easily. And having a tracer
to use, worked like a treat.

Paul

I have a Progressive 700C telephone wiring trace kit (leftover from another
career) which proves useful for such things and that is how I got my CAT-5E
cables under control. It has even come in handy for tracing AC cables
insides walls and ceilings although one has to be more than a bit careful.
It actually shows where the wires are rather than my other kit which simply
shows which breaker is attached to a given outlet or socket. Of course when
the tough get going nothing beats knocking holes in the walls to see where
the cables actually run...