§  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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