FutureSmart Wire Certification
"Structured Wiring, that is your Gateway
to the Future"
Tree Ridge Enterprise handles FutureSmart® wire certification:
- Certification of new
installations
- Insuring that existing cabling will support the network
- Verify cabling performance for network upgrades
- Troubleshooting network problems
What is involved in testing cable?
Measuring the electrical characteristics of network cabling,
typically using a hand-held field tester designed specifically for the
application. The cable is tested to a specific standard,
category, or class,
and results are compared to performance criteria established by recognized
standards organizations.
What are "Categories"?
Categories designate the performance characteristics and
quality of network cabling. EIA/TIA standards bodies currently define
3 categories of twisted pair cabling for voice and data applications:
- Category 3: 10 Mbps; cable and components rated for 0-16
MHz transmission frequencies
- Category 4: 16 Mbps; cable and components rated for 0-20
MHz transmission frequencies
- Category 5: 100 Mbps; cable and components rated for
0-100 MHz transmission frequencies
Currently Recognized Cabling
Standards:
ANSI / EIA / TIA-568A
Category 3,4,5 Basic Link
Category 3,4,5 Channel (BL + Patch Cords)
Other Cable Test Standards:
ISO 11801 Class C,D (Europe)
AS/NZ 3080 Class C,D (Australia / New Zealand)
ScTP Class C,D (Europe)
FTP 120 Ohms (Europe)
J IS X 5150 (Japan)
Euro Normative EN-50173
Network specific tests to verify cabling performance on an existing network:
10BASE-2, 10BASE-5, 10BASE-T,
100BASE-Tx, 100BASE-T4
Token Ring 4Mbps / 16Mbps
100 VG-Any LAN
TP-PMD
TP-PMD Reversed
ATM 155 Mbps
Certification Requirements:
TSB-67 currently requires (as a minimum) the following
tests:
Wire Map (connectivity)
Length (conductor length)
Attenuation (signal loss)
NEXT (near-end cross-talk)
Testing Wire Map - Tester provides a graphical display
of the cable's physical connectivity:
Reversed Wires
Crossed Wires
Open Wires
Shorted Wires
Split Pairs
Testing electrical length
· Time Domain Reflectrometry (TDR) measures cable length; length limits
are set by cable standards. TDR also finds anomalies by detecting changes
in impedance along the cable.
Testing signal attenuation
· Attenuation is a measure of signal loss along the cable. Attenuation
is directly related to cable length and frequency of transmission.
Testing for crosstalk · Near
End Cross Talk (NEXT) is a measure of how much unwanted signal is coupled
onto adjacent wire pairs (pair-to-pair NEXT) and is usually associated
with cable termination points and connectors. Two-way testing systems
measure from both cable ends.
What does the future hold for network cabling systems?
Emerging cabling systems (e.g. "Enhanced" Cat
5) exhibit vastly improved NEXT, return loss and attenuation performances,
and channel bandwidths of 200 MHz or more.
What impact will improved cabling systems have on certification
testing?
The upcoming standards demand much higher performance
from cabling and connecting hardware than Cat 5. The new standards require
the use of hand-held field testers that are more sophisticated than current
CAT 5 products and may require a "homogenous" or "system
matched" premise wiring infrastructure.
When are the new standards going to be ratified?
Ratification will most likely occur by 2001. Additional
test parameters will be included and the standards will vary slightly
depending upon the standards bodies (US, Europe, etc).
What can we expect to see from the EIA/TIA Standards
Organization?
Ratification of TSB-95 "Additional Transmission Performance
Guidelines for 100 Ohm 4-pair Cat 5 Cabling" and of 568-A-5 "Additional
Transmission Performance Specifications for 4-pair 100 Ohm Cat 5e Cabling".
TSB-95 is for re-certification of existing Category 5 installations using
new tests and test parameters; 568-A-5 is for certification of new Enhanced
Category 5 (Cat 5e) installations.
What additional tests are required for new standards?
Propagation Delay, Delay Skew, Attenuation to Crosstalk
Ratio (ACR), PowerSum Measurements, Far End Crosstalk (FEXT), Equal Level
Far End Crosstalk (ELFEXT) and Return Loss.
Testing Propagation Delay and Delay
Skew · Propagation Delay measures the time it takes for a signal
to travel from transmit to the end of the cable. Propagation Delay Skew
is the time difference between arrival of the first signal on a wire pair
and subsequent signals from the remaining pairs.
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Designers