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Report #70112.e1 

 
 

 
3.2.1 Object 

The purpose of this test is to measure the conducted electromagnetic emissions on the AC power 
lines, pursuant to FCC part 15 and EN55022 Class B requirements. (See Table 3.2.1-1 for the 
Class B conducted limits.) 
 

 

Testing is performed in an Open Area Test Site. Equipment is arranged on the table as described 
in section 3.1.2. Each individual current-carrying power lead shall be individually connected 
through a 50

Ω/50µH Line Impedance Stabilization Network (LISN). A 2-meter x 2-meter vertical 

coupling plane is placed 40 cm to the rear of the EUT. The EUT is set into operation such that all 
parts of the system are exercised, while the RF voltages across the 50 

Ω measuring port of the 

LISN are recorded. The test is repeated for each current-carrying power line of the EUT. 
 

 

None 
 

A minimum of a 1 dB margin of compliance is recommended for conducted emissions data to 
verify passing results. This is recommended to compensate for the measurement uncertainties 
involved. 

Report #70112.e1 

 
 

 

The Digital Controller met the FCC, VCCI, and EN55022 Class B conducted emissions 
requirements when tested as described below. (See Test Data for a complete listing of data 
points.) 
 
Worst-case emissions measured:  

Modifications 

Conducted Emissions 

Conducted Emissions 

See Note (1) 

Passed: - 4.6dB at 6.35 MHz 

Line Voltage: 120 VAC 60 Hz 

See Table: A2 

Passed: - 4.3dB at 6.15 MHz 

Line Voltage: 230 VAC 50 Hz 

See Table: A3 

 
Notes 
 
 

(1) 

Final scan. No modifications installed. 

 
 
The above results pertain only to the specific item submitted for testing, identified by the 
product’s model and serial numbers. 

Report #70112.e1 

 
 

 
The following is a description of terms and a sample calculation, as appears in the conducted 
emissions data table. The numbers used in the calculation are for example only. There is no direct 
correlation to the specific data taken for the product described in this document: 
 
Reading:  This is the reading obtained on the spectrum analyzer in dB

µV. Any external 

attenuators used are taken into account through internal analyzer settings. 

 
Limit: 

This is the FCC Class B conducted emission limit (in units of dB

µV). 

 
Margin:  This is the margin of compliance below the FCC limit. The units are given in dB. A 

negative margin indicates the emission was below the limit. A positive margin indicates 
that the emission exceeds the limit. 

 
Example for an emission measuring 55 dB

µV on the spectrum analyzer at 5.4 MHz: 

(Note: This shows a passing result (i.e. a negative margin)) 
 
Example only: 
 

Reading                FCC limit 

       Margin 

55 dB

µV    -         60 dBµV     =        -5 dB 

Report #70112.e1 

 

 

 

 

µV/m) 

µV/m) 

30 to 88 

40 

30 

40 

30 

88 to 216 

44 

33 

40 

30 

216 to 230 

46 

36 

40 

30 

230 to 960 

46 

36 

47 

37 

960 to 1000 

54 

44 

47 

37 

Above 1000 

*54 

*44 

N/A 

N/A 

 
 

 

* Average detector used. 

 

 
 

.15 MHz to .5 MHz 

56 dB

µV to 46 dBµV 66 

dB

µV to 56 dBµV 

.5 MHz to 5 MHz 

46 dB

µV 56 

dB

µV 

5 MHz to 30 MHz 

50 dB

µV 60 

dB

µV 

 
 

(Note: For each table shown above, the stricter limit applies at the frequency transition points.)