LED VIDEO WALL CERTIFICATION of America standard FCC Certificate

LED VIDEO WALL CERTIFICATION of America standard FCC Certificate

As we know that America is very strick on all products quality that being imported to its Country . EXCEL LED has been in LED Industry for over 12 Years and we never compromise on quallty , as a responsible and reliable LED Video Wall manufacturer we  appeal that every manufacturer in this industry should meet the LED Video Wall Certification of FCC .

FCC LED Video Wall Certification of EXCEL LED Tested products models in above . 

What is  FCC ?

The full name of FCC is the Federal Communications Commission. Established in 1934 under the Communications Act, it is an independent agency of the United States government directly responsible to Congress. The FCC coordinates domestic and international communication by controlling radio broadcasting, television, telecommunications, satellites, and cables. In order to ensure the safety of radio and wired communication products related to life and property in more than 50 states, Colombia, and affiliated regions of the United States, the Office of Engineering and Technology of the FCC is responsible for the technical support of the committee, as well as equipment accreditation matters. Many wireless application products, communication products, and digital products require FCC approval to enter the US market. The FCC committee investigates and studies the various stages of product safety to identify the best ways to solve problems, while also including radio equipment, aircraft testing, and so on.

What will be tested and indentifed with the Certification of FCC ?

The technical report submitted to the FCC includes performance indicators such as RF output power, modulation characteristics, occupied bandwidth, stray emissions from antenna ports, stray radiation field strength, frequency stability, and spectral characteristics. FCC regulations generally specify the limits and testing requirements for each performance indicator, and only briefly introduce the corresponding testing methods.

RF output power 

According to the power regulation program, adjust the voltage and current values fed into the RF amplification circuit to ensure it is in the maximum rated power transmission state, and add appropriate loads to the RF output port to test the maximum RF output power. The method of power adjustment will vary for different emission types, and this should be explained in detail in the technical report of led video wall .

Modulation characteristics 

(1) For communication  products with voice modulation, it is necessary to measure the frequency response curve of the audio modulation circuit within the frequency range of 100-5000Hz. If the product uses an audio low-pass filter, the frequency response curve of the audio filter should also be measured.

(2) For  Products that use modulation restriction processing, it is necessary to measure the modulation percentage input voltage relationship curve within the entire modulation frequency and signal power level range.

(3) For wireless telephone transmitters using single sideband and independent sideband limiting peak envelope power circuits, the relationship curve between peak envelope output power and input voltage needs to be measured.

(4) Other types of products will be processed according to the certification type applied and corresponding regulations.

Bandwidth occupied

When measuring bandwidth usage, the measurement method may vary for products using different modulation methods. However, the basic principle is to select a typical business mode where the modulation signal has the maximum amplitude for testing, and provide a detailed explanation of the input modulation signal in the report.

Spurious emission from antenna ports

In addition to the RF power or voltage at the useful frequency points of the product, it is also necessary to measure the useless stray frequencies. When measuring, a suitable fake antenna can be added to the antenna output port; Harmonics and some significant stray emission points need to be given special attention.

Stray radiation field strength

This test mainly detects the harmonics of the product casing port, control circuit module, and power port, as well as the field strength of some significant stray emission frequency points. For products with operating frequencies below 890MHz, measurements need to be conducted in an open field or anechoic chamber. For on-site testing, it is necessary to conduct detailed investigation, analysis, and explanation of the RF sources and obvious reflective objects near the measurement site.

Frequency stability

The frequency stability that needs to be checked includes the frequency determination of the product and the frequency variation of the stable circuit when the environmental temperature and input voltage change. In special cases, it may also include the frequency stability of the product when equipped with different antennas or moving near large metal objects.

The range of temperature change is -30 ℃ to+50 ℃, and the measured temperature interval is not greater than 10 ℃. When measuring the frequency of each temperature point, it is necessary to wait long enough for the components related to the resonant circuit to reach a stable state.

The range of voltage variation is 85% to 115% of the rated working voltage. For portable products that rely on batteries for operation, the minimum voltage can be the cut-off voltage.

Spectral characteristics

The spectral range for evaluating and measuring stray emission and radiation field strength will be determined based on the operating frequency of the product. The lowest frequency for conducting spectral feature research can be chosen as the lowest frequency point actually used by the product; If the minimum frequency is below 9kHz, then 9kHz is chosen as the lowest frequency point for the study. The selection of the highest frequency follows the following principles:

(1) For products with operating frequencies below 10GHz, the 10th harmonic with the highest fundamental frequency is selected as the highest frequency for evaluation. If the frequency of the 10th harmonic is greater than 40GHz, 40GHz is selected as the highest frequency for evaluation.

(2) For products with operating frequencies between 10GHz and 30GHz, the 5th harmonic of the highest fundamental frequency is selected as the highest frequency for evaluation. If the frequency of the 5th harmonic is greater than 100GHz, 100GHz is selected as the highest frequency for evaluation.

(3) For products with operating frequencies above 30GHz, the 5th harmonic of the highest fundamental frequency is selected as the highest frequency for evaluation. If the frequency of the 5th harmonic is greater than 200GHz, 200GHz is selected as the highest frequency for evaluation.

The TABLE OF CONTENT in LED Video Wall Certification of FCC :

GENERAL INFORMATION in LED VIDEO WALL CERTIFICATION OF FCC :

MEASURING DEVICE AND TEST EQUIPMENT in LED VIDEO WALL CERTIFICATION OF FCC

POWER LINE CONDUCTED EMISSION MEASUREMENT in LED VIDEO WALL CERTIFICATION OF FCC :

CONDUCTED EMISSION TEST DATA in LED VIDEO WALL CERTIFICATION OF FCC :

RADIATED EMISSION MEASUREMENT :