§ 15.207   Conducted limits.

   (a) Except as shown in paragraphs (b) and (c) of this section, for an
   intentional radiator that is designed to be connected to the public
   utility (AC) power line, the radio frequency voltage that is conducted
   back onto the AC power line on any frequency or frequencies, within the
   band 150 kHz to 30 MHz, shall not exceed the limits in the following
   table, as measured using a 50 μH/50 ohms line impedance stabilization
   network (LISN). Compliance with the provisions of this paragraph shall
   be based on the measurement of the radio frequency voltage between each
   power line and ground at the power terminal. The lower limit applies at
   the boundary between the frequency ranges.
   Frequency of emission (MHz) Conducted limit (dBμV)
                               Quasi-peak  Average
   0.15-0.5                    66 to 56*  56 to 46*
   0.5-5                       56         46
   5-30                        60         50

   *Decreases with the logarithm of the frequency.

   (b) The limit shown in paragraph (a) of this section shall not apply to
   carrier current systems operating as intentional radiators on
   frequencies below 30 MHz. In lieu thereof, these carrier current
   systems shall be subject to the following standards:

   (1) For carrier current system containing their fundamental emission
   within the frequency band 535-1705 kHz and intended to be received
   using a standard AM broadcast receiver: no limit on conducted
   emissions.

   (2) For all other carrier current systems: 1000 μV within the frequency
   band 535-1705 kHz, as measured using a 50 μH/50 ohms LISN.

   (3) Carrier current systems operating below 30 MHz are also subject to
   the radiated emission limits in § 15.205, § 15.209, § 15.221, § 15.223, or
   § 15.227, as appropriate.

   (c) Measurements to demonstrate compliance with the conducted limits
   are not required for devices which only employ battery power for
   operation and which do not operate from the AC power lines or contain
   provisions for operation while connected to the AC power lines. Devices
   that include, or make provisions for, the use of battery chargers which
   permit operating while charging, AC adapters or battery eliminators or
   that connect to the AC power lines indirectly, obtainig their power
   through another device which is connected to the AC power lines, shall
   be tested to demonstrate compliance with the conducted limits.

   [ 54 FR 17714 , Apr. 25, 1989, as amended at  56 FR 373 , Jan. 4, 1991;  57 FR 33448 , July 29, 1992;  58 FR 51249 , Oct. 1, 1993;  67 FR 45671 , July
   10, 2002]

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