TYPE
PRODUCT SPECIFICATION
NUMBER
GS-12-083
TITLE
Single and Multi-Port Modular Jack Assemblies
PAGE
REVISION
11 of 18
F
AUTHORIZED BY
DATE
B. Brubaker
27 Mar 01
CLASSIFICATION
UNRESTRICTED
Copyright 2001 FCI USA, INC.
Form E-3334
02/12/01
GS-01-001
Connector return loss is a measure of the degree of impedance matching between the
cable and connector and is derived from swept frequency voltage measurements on short
lengths of 100
twisted-pair test leads before and after inserting the connector under
test. A balanced input signal is applied to a connector pair while signals that are
reflected back due to impedance discontinuities are measured at the same port from
which the signal is applied. The same set-up that is used for NEXT loss measurements
is also used for return loss, except that only a single connection is made to the network
analyzer.
Because the return loss characteristics of category 3 connector hardware are not
considered to have a significant effect on the link performance of category 3 UTP cabling,
return loss requirements are not specified for category 3 connectors.
For category 4 and 5 connectors, the minimum return loss shall be 23 dB or greater for
frequencies between 1 and 20 Mhz. For frequencies from 20 to 100 Mhz, category 5
connectors shall exhibit a minimum return loss of 14 dB or greater. These return loss
values are chosen to limit peak reflected voltage to 7% or less up to 20 Mhz and to 20%
or less from 20 to 100 Mhz.
6.7.4
DC Resistance
The DC resistance between the input and output connections of the connecting hardware
(not including the cable stub, if any) used for 100
cabling shall not exceed 0.3
when
tested in accordance with ASTM D 4566.
NOTE: DC resistance is a separate measurement from the contact resistance
measurements required in normative Annex A. Whereas DC resistance is measured to
determine the connector’s ability to transmit direct current and low frequency signals,
contact resistance measurements are used to determine the reliability and stability of
individual electrical connections.
6.8
Current Rating and Current Carry Capacity - The temperature rise above ambient shall not exceed
30 degrees C at any point in the system when all contacts connected in series are powered a 1
ampere(s). The following details shall apply:
a) Ambient Conditions - still air at 25 degrees C
b) Reference - BUS-03-601
c) Connector derating curve shall be as shown in Figure 5