Using the DTX CableAnalyzer
and the optional fiber modules in the back.
You'll notice on the table here I have
my inspection and cleaning equipments.
I've already inspected and cleaned
my test reference cords.
Without the inspection equipment
it's going to get very unpredictable.
You'll notice I use the term 'test
reference cord' and not 'patch cord',
that's because I'm talking about cords
which have reference-grade connectors
on them. According to ISO/IEC 14763-3,
for Multimode these need to be
better than 0.1 dB, and for
Singlemode better than 0.2 dB.
Now, even if you're testing to the TIA standard,
you should aim for 0.1 and 0.2 dB,
because that's going to get you
consistent, reliable test results.
So, the first thing I'm going to do
is connect it to my main unit.
And here you'll see this red device.
This is a mandrel.
You need to be using mandrels.
If you don't, your results are
going to be pessimistic.
So, the mandrel end is connected
to the output port on the main unit,
and then we're going to connect
directly into the remote unit.
We are not going to set a reference
through a bulkhead adapter.
I have a 50/50 chance
of getting this right.
These are Fluke TRCs, so red is hot,
which is the output. Black is cold,
which is the input. So I'm going
to take my black and connect it
to the input on the remote unit here.
Then I'm going to take my other
test reference cord and do exactly
the same but from the other end.
So, with the mandrel, red is hot,
so that goes to the output port.
And then the other end of my test
reference cord, again, 50-50 chance,
but since these are Fluke TRCs,
we know that red goes to black,
Hot to cold.
And that chirp indicates
that I got the polarity correct.
So let's talk about setting up
your DTX CableAnalyzer.
So, we're going to rotate the dial
to 'set up', and with 'Fiber Loss'
highlighted we're going to hit
the ENTER key.
My test limit is currently selected to TIA
and that's what I'm going to be using today.
But, if I was to test to the ISO/IEC
14763-3 standard,
I would hit the ENTER key,
f1, 'More',
and go and select the 'ISO' folder,
where I'll find my standard.
My next selection in here is my fiber type.
It's currently set to OM2
and as you can tell by the cables
I'm testing OM3 fiber today.
so I need to change that to OM3.
That's going to impact what shows up
at the bottom my link where tests' report.
At the bottom of the link where
tests' report, you're going to see
a list of supported applications
for the fiber you just tested.
If I'd left that at OM2 fiber
and the link was greater than 82 meters,
then 10GBASE-SR would not show up
at the bottom of the test report.
But, by selecting OM3 fiber,
as long as that link is no greater
than 2.6 dBm loss
and is 300 meters or less in length,
then I will see 10GBASE-SR
show up at the bottom of the test report.
My other options here are Remote End
Setup, it's set to Smart Remote
because I'm doing duplex testing,
and bi-directional testing.
This is not a requirement in TIA or ISO,
however, your consultant or end-user
may specify this, so please check with
whoever wrote the test specification.
Let's go across to tab number 2,
where we see the number of adapters.
This is going to impact your test limit,
so this is important to get this correct.
This is the number of bulkhead adapters
added after you set the reference
per fiber path.
Sounds complicated? Not really.
We are setting a reference,
but we're not setting it
through a bulkhead adapter,
and the link we're testing has a
bulkhead adapter at one end
and a bulkhead adapter at the other end,
so our adapter count is going to be two.
The number of splices is set at zero,
even if I'm using mechanical connectors
such as UniCams. They have a mechanical
splice built into the connector,
but that's part of your allowable loss.
The only time you would enter
a splice in here, is if you're doing
fusion splicing with pigtails,
or indeed there is a splice
in the middle of your link.
The connector type is set to SC,
since that's what we're testing today,
and that's not going to affect
the outcome of the test result,
but it will affect the help screens
that are going to appear on your DTX.
And then finally our test method,
one jumper, because we're jumping
from the main to the remote in one go.
We're not going through a bulkhead adapter.
We're going to do one jumper
per the TIA and ISO/IEC standards.
And then finally tab number 3,
we have the index of refraction.
That's going to affect the length
reported by the DTX CableAnalyzer.
I recommend that you go to the cabling
vendor's website and get the latest
datasheet for that fiber,
and make sure the values match up.
If they don't, this is the menu where
you would change those values.
Okay, so we're ready to set a reference.
My sources have been switched on
and been allowed to stabilize for
at least 5 minutes. It may take longer
if these were stored in a colder condition.
So we 'Set Reference' highlighted,
I hit the ENTER key,
it draws a picture of my setup,
and then I hit TEST.
And now what it's going to do
is it's going to reference out
the connection to the output ports
and the fiber between the two testers.
And it's going to come back with
some power loss values. They're
power loss because they're in dBm,
dB milliwatts. Now, as a guide,
if it's 50 micron you want these
to be better than -24 1/2 dBm,
where -22 1/2 dBm is better.
If you're doing 62 1/2 micron
you want it better than -20 dBm,
and if you're doing Singlemode
you want it better than -8 dBm.
And if you're doing Singlemode,
make sure that your cords are laid out
straight, otherwise you're not going to
hit the desired values, and potentially
end up with negative loss readings.
So, I'm good with these values here.
I'm going to press f2.
I can put in the length of the cords
that I'm using here. Again, it's not
going to impact the outcome
of the test result, but it will show up
on your test report. f2, 'OK'.
Now, what I want to do is I want
to make sure my sources are stabilized.
So I'm going to rotate the dial
to 'auto test' and run a test.
And if the sources have stabilized
then I should see 0 dB loss
for each fiber path.
The input fiber is the input fiber
on the main unit, and that is showing
a loss of 0 and 0 dB.
I'm ignoring the pass and
the limits in the margins.
I just want to look at the loss values
and make sure they're 0.
They are, so that tells me my
source on my remote unit is stabilized.
On the output fiber, again on the
main unit, we're seeing 0 and 0dB loss.
that means that my source is now
stabilized on my main unit.
So the next step in the process,
what we're going to do is disconnect
the fibers from the input ports.
So, I'm going to disconnect it
from the input port on the main unit
and put my protective cap on there.
I'm also going to disconnect it
from the input port on the remote unit.
And, again, carefully put my cap on there
to protect the end fiber.
Then, on the main unit,
where the mandrel is, adjacent to that,
you'll finds your SC connector here,
which is also black, which goes to the
input port because that's cold.
And we'll do the same
on the remote as well.
So, from the remote unit, I now have
duplex cords. And on my main unit here
I also have duplex cords. So I could
just go off and plug this into
my patch panel at one end
and these to my patch panel
at the other end. The problem is,
I don't actually know how good these cords are.
So what I want to do is I want to
check out to make sure these are good.
So, even though I'm doing Multimode,
I'm going to use a Singlemode-rated
bulkhead adapter and I'm going to connect
the main and the remote units together,
remembering black to red red to black.
I get this right again we'll hear a chirp.
Okay, so what I'm going to do now
is I'm going to run a test to see
what the loss is in this connection here,
and hopefully it's better than 0.1 dB,
because that's what we want for Multimode.
If it was Singlemode, we want better
than 0.2 dB. Again, in Singlemode
make sure the cords are laid out straight.
TEST.
And, again, I'm hoping for 0.1 dB or better.
And our input fiber, which is our
input fiber to the main unit,
is 0.01 and 0.01, which means
this is a near-perfect test reference
cord on that fiber path.
Not forgetting to go and check
our other fiber.
0.09 and 0.08, excellent.
Exactly where we want to be.
So I know that my test reference cords
are in good condition.
Now, there is a good idea here
to tell the technician to save
these two test results as TRC1 and TRC2,
or something similar, and include them
as part of your test results package.
That way, everybody knows that the
test reference cords were in good condition
when the testing was conducted.
Okay, on to the final step.
We know our test reference cords are good,
so disconnected it from the
bulkhead adapter in the middle.
Very important to protect our fibers,
so I'm going to cap them.
Especially if I'm on a building site.
Do the same for the remote as well.
And then this end will be taken to
one patch panel and this to the
other end of the patch panel,
and then you could run a test.
And that is how you would
successfully test an SC to SC
duplex fiber link, using the
DTX CableAnalyzer and the
one jumper reference method.