FCC PART68 number 中的REN 是什么意思
请问一下FCC part 68 number 中的REN 是什么意思，代表什么参数 Ringer equivalence numberhttp://en.wikipedia.org/wiki/Ringer_equivalence_number
In telecommunication, a ringer equivalence number (REN) is a somewhat arbitrary number which denotes the electrical load a telephone ringer has on the line. In the U.S., this is determined in accordance with ANSI/TIA-968-B (August 2009).
REN is a United States-developed yardstick, but analogous systems exist internationally. In some countries, (particularly in Commonwealth nations), the REN is better known as the ringer approximated loading number (RAL).
In the United Kingdom it is called the ringer equivalence number and a maximum of 4 is allowed on any British Telecom (BT) line.
In Canada it is called a Load Number (LN); which cannot exceed 100. (The LN of each device represents the percentage of total load allowed).
In the United States 1 REN was formerly equivalent to a 6930Ω resistor in series with an 8 µF (microfarad) capacitor. The modern ANSI/TIA-968-B specification (August 2009) defines 1 REN as an impedance of 7000Ω at 20Hz (type A), or 8000Ω from 15Hz to 68Hz (type B).
In Europe 1 REN used to be equivalent to an 1800Ω resistor in series with a 1 µF capacitor. The latest ETSI specification (2003-09) calls for 1 REN to be greater than 16 kΩ at 25 Hz and 50 Hz. 引用第1楼H-RH于2011-04-28 13:34发表的:
Ringer equivalence number
http://en.wikipedia.org/wiki/Ringer_equivalence_number
In telecommunication, a ringer equivalence number (REN) is a somewhat arbitrary number which denotes the electrical load a telephone ringer has on the line. In the U.S., this is determined in accordance with ANSI/TIA-968-B (August 2009).
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谢谢H-RH. 楼上说的很清楚了
谢谢
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