§ 18.307   Conduction limits.

   For the following equipment, when 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 shall not exceed the
   limits in the following tables. 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 using a 50 μH/50
   ohms line impedance stabilization network (LISN).

   (a) All Induction cooking ranges and ultrasonic equipment:
   Frequency of emission (MHz) Conducted limit (dBμV)
                               Quasi-peak  Average
   0.009-0.05                  110        —
   0.05-0.15                   90-80*     —
   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) All other part 18 consumer devices:
   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.

   (c) RF lighting devices:
   Frequency (MHz) Maximum RF line voltage measured with a 50 uH/50 ohm LISN
   (uV)
   Non-consumer equipment:
   0.45 to 1.6 1,000
   1.6 to 30 3,000
   Consumer equipment:
   0.45 to 2.51 250
   2.51 to 3.0 3,000
   3.0 to 30 250

   (d) If testing with a quasi-peak detector demonstrates that the equipment
   complies with the average limits specified in the appropriate table in this
   section, additional testing to demonstrate compliance using an average
   detector is not required.

   (e) These conduction limits shall apply only outside of the frequency bands
   specified in § 18.301.

   (f) For ultrasonic equipment, compliance with the conducted limits shall
   preclude the need to show compliance with the field strength limits below 30
   MHz unless requested by the Commission.

   (g) The tighter limits shall apply at the boundary between two frequency
   ranges.

   [ 50 FR 36067 , Sept. 5, 1985, as amended at  52 FR 43198 , Nov. 10, 1987;  64 FR 37419 , July 12, 1999;  67 FR 45671 , July 10, 2002]

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