FCC Part 15 Conducted Emission (CE) Limits
FCC Section 15.107 – Conducted Limits
Quick reference for the exact FCC Part 15 limit (Section 15.107 Conducted Emissions). View Quasi-peak and Average limits for Class A and Class B digital devices.
Class B (Residential / Commercial)
* For Class B devices, in the 0.15 to 0.50 MHz range, the limit decreases linearly with the logarithm of the frequency.
Class A (Industrial)
FCC Part 15 Conducted Emission Overview
FCC Part 15.107 specifies the limits for radio frequency voltage that is conducted back onto the AC power line. These regulations ensure that digital devices do not interfere with other equipment connected to the same power network.
Class A Digital Device: A digital device that is marketed for use in a commercial, industrial or business environment, exclusive of a device which is marketed for use by the general public or is intended to be used in the home.
Class B Digital Device: A digital device that is marketed for use in a residential environment notwithstanding use in commercial, business and industrial environments. Class B limits are more stringent than Class A.
How to read this FCC Part 15 reference
User task
Use this page to compare a conducted RF-voltage reading from an AC-powered digital device with the Class A or Class B limits in 47 CFR § 15.107. The table is organized around the power-line measurement, not around a generic EMC pass/fail claim.
Choose before comparing
First identify the device class and confirm that the measurement is made between each AC power line and ground at the power terminal. A 50 µH/50 ohms LISN is part of the cited FCC measurement context; a battery-only device that never operates from an AC line is treated differently by § 15.107(d).
What the displayed rows mean
- Class B, § 15.107(a)
- 150 kHz–30 MHz; the 150–500 kHz values are frequency-dependent endpoints (66→56 dBµV QP and 56→46 dBµV average), followed by 56/46 and 60/50 dBµV bands.
- Class A, § 15.107(b)
- 150 kHz–30 MHz; 79/66 dBµV applies from 150–500 kHz and 73/60 dBµV from 500 kHz–30 MHz.
- Boundary handling
- The lower limit applies at a band boundary. Do not treat a range such as 66→56 as one flat 66 dBµV threshold or mix the Class A and Class B rows.
Common misread
A conducted limit is not a radiated-field limit: it does not use an antenna distance or dBµV/m. Carrier-current systems below 30 MHz and devices with indirect AC connection have additional conditions in the rule text, so this table should not be used as a complete authorization decision.
Reference boundary
EMCCalc transcribes the cited limit rows and explains how to select them. It does not replace the current FCC rule, the complete measurement procedure, or a formal Supplier’s Declaration of Conformity/certification assessment.
Content review date:
Need to convert units for this standard?
Try our free RF 50Ω Calculator and Voltage Converter. Instantly convert between dBµV, dBm, V/m, and more.
Source and verification
- Primary source
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Electronic Code of Federal Regulations — 47 CFR § 15.107 Subpart B, § 15.107 (Conducted limits)
- Applicability
- Unintentional radiators / digital devices; Class A and Class B limits are shown separately.
- Read this limit with
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- AC mains power port
- 0.15–30 MHz
- Quasi-peak and average detectors
- dBµV
- Class B 0.15–0.50 MHz values follow the frequency-dependent line
- Last source-link and context review
- Verification method
- The source link, edition/section locator, and measurement context were reviewed against the values shown here. This reference is not a formal conformity assessment or certification.
Engineering reading
Choose the correct equipment class, port, detector, frequency range, facility, and distance before comparing a measurement to a limit.