English for Overcurrent Circuit Protection

-compliance with safety agency standards
-provide a uniform protocol for the addition and configuration of computer peripherals
-The USB is viewed as an inexpensive system for
-It is designed to accommodate transmission rates up to
-can be powered by a hub through the communication cable without additional power inputs
-The bus is designed to sense the addition or removal of a USB-compliant device and then automatically configure accordingly.
-select the correct components in conjunction with
(1)resettable polymer PTCs (positive-temperature-coefficient devices), (2)fuses, and (3) regulated networks
-the most commonly employed solutions
-Fuses are one-time devices
-a fuse will provide protection from an overload only once, then it needs to be replaced.
-The heart of a traditional fuse is a metal element that is heated to its melting point by any excessive current.
-The circuit current flow decreases to zero as the element melts open, destroying the fuse.
-The PTC also reacts to the occurrence of excessive current, but unlike the fuse is a resettable device.The PTC also reacts to the occurrence of excessive current, but unlike the fuse is a resettable device.
-The PTC's conductive polymer increases in resistance when heated by an overload, and this limits the circuit current. When the power source is removed, the device resets itself.
-Regulated networks, or power-distribution switches, which combine a number of functions in one package, have also been put forward as resettable solutions for port protection.
-limiting potentially damaging overcurrent when the current exceeds the specified rating.
-in this respect
-The USB standard organization defines a nominal operating voltage of 5 V and a hub operating current of 0.500 A per port.