User`s manual

Reference No T11112830801-RE
Report No T11112830801-RE
Page 24 /
50
7.3 CONDUCTED EMISSION MEASUREMENT AT
TELECOMMUNICATION PORTS
LIMITS
The telecommunication ports shall meet the class B limits given in EN 55022 [1].
Voltage Limit
(dBuV)
Current Limit
(dBuA)
Frequency
(MHz)
Quasi-peak Average Quasi-peak Average
0.15 - 0.5 84 ~ 74 74 ~ 64 40 ~ 30 30 ~ 20
0.5 - 30.0 74 64 30 20
Note: The limits decrease linearly with the logarithm of the frequency in the range 0,15 MHz to 0,5 MHz.
Alternatively, for equipment intended to be used in telecommunication centres only, the class A limits
given in EN 55022 [1] may be used.
Voltage Limit
(dBuV)
Current Limit
(dBuA)
Frequency
(MHz)
Quasi-peak Average Quasi-peak Average
0.15 ~ 0.5 97 ~ 87 84 ~ 74 53 ~ 43 40 ~ 30
0.5 ~ 30.0 87 74 43 30
NOTE: The limits decrease linearly with the logarithm of the frequency in the range 0.15 MHz to 0.5 MHz.
TEST PROCEDURE
Selecting ISN for unscreened cable or a current probe for screened cable to take
measurement.
The port of the EUT was connected to the remote side support equipment through the
ISN/Current Probe and communication in normal condition.
Making a overall range scan by using the test receiver controlled by controller and record
at least six highest emissions for showing in the test report.
Emission frequency and amplitude were recorded into a computer in which correction
factors were used to calculate the emission level and compare reading to the applicable
limit.
In case of measuring on the screened cable, the current limit shall be applied; otherwise
the voltage limit should be applied.
The following test mode was scanned during the preliminary test:
Mode:
1. LAN 10Mbps
2 LAN 100Mbps
3 WAN 10Mbps
4 WAN 100Mbps
After the preliminary scan, we found the following test mode(s) producing the highest
emission level and test data of the worst case was recorded.
Mode 1; 2; 3; 4