ELPRO 215U-2, Руководство пользователя

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User Manual MN032EN
Effective October 2017
215U-2 802.11
wireless I/O and gateway
EATON
www.eaton.com
Glossary
Term Definition
802.11 A standards for
wireless networking
allowing high speed wireless
connection between devices.
ACK
Acknowledgment.
Access Point An access point connects wireless network stations (or clients) to other stations within the wireless network and also can serve as
the point of interconnection between the wireless network and a wired network. Each access point can serve multiple users within a
defined network area. Also known as a base station.
Antenna Gain Antennas do not increase the transmission power, but instead focus the signal. Rather than transmitting in every direction (including
the sky and ground), antenna focus the signal either more horizontally or in one particular direction. This gain is measured in decibels.
AWG
American wire gauge (AWG), also known as the Brown and Sharpe wire gauge, is a standardized wire gauge system used
predominantly in the United States and Canada for the
diameters of round, solid, nonferrous, electrically conducting wire.
Bandwidth The maximum data transfer speed available to a user through a network.
COS Change of state. For a digital input, a COS is a change from “off” to “on,” or a change from “on” to “off.” For an analog input, internal
analog input, or pulse input rate, a COS is a configurable value called sensitivity.
CSA The Canadian Standards Association (CSA), is a not-for-profit standards organization that develops standards in 57 areas. The
CSA registered mark shows that a product has been independently tested and certified to meet recognized standards for safety or
performance.
DCS A Distributed Control System (DCS) is a computerized control system used to control the production line in industry. The entire system
of controllers is connected by networks for communication and monitoring.
DHCP
Dynamic Host Configuration Protocol is a utility that enables a server to dynamically assign IP addresses from a predefined list and limit
their time of use so that they can be reassigned. Without DHCP, an IT manager would need to manually enter in all the IP addresses
of all the computers on the network. When DHCP is used, whenever a computer logs onto the network, an IP address is automatically
assigned to it.
DIO Digital input/output.
DIN Rail A DIN rail is a metal rail of a standard type widely used for mounting circuit breakers and industrial control equipment inside equipment
racks.
DNS Domain name service (DNS) is a program that translates URLs to IP addresses by accessing a database maintained on a collection
of Internet servers. The program works behind the scenes to facilitate surfing the Web with alpha versus numeric addresses. A DNS
server converts a name like mywebsite.com to a series of numbers like 107.22.55.26. Every website has its own specific IP address on
the Internet.
Encryption Key An alphanumeric (letters and/or numbers) series that enables data to be encrypted and then decrypted so it can be safely shared
among members of a network. WEP uses an encryption key that automatically encrypts outgoing wireless data. On the receiving side,
the same encryption key enables the computer to automatically decrypt the information so it can be read. Encryption keys should be
kept secret.
EIRP
Equivalent isotropically radiated power (EIRP) or, alternatively, effective isotropically radiated power is the amount of power that a
theoretical isotropic antenna (which evenly distributes power in all directions) would emit to produce the peak power density observed
in the direction of maximum antenna gain. EIRP can take into account the losses in transmission line and connectors and includes the
gain of the antenna. The EIRP is often stated in terms of decibels over a reference power emitted by an isotropic radiator with an
equivalent signal strength. The EIRP allows comparisons between different emitters regardless of type, size or form.
Hub A multiport device used to connect PCs to a network via Ethernet cabling. Wired hubs can have numerous ports and can transmit data
at speeds ranging from 10 Mbps to multi-Gigabyte speeds per second. A hub transmits packets it receives to all the connected ports. A
small wired hub may only connect four computers; a large hub can connect 48 or more.
Hz Hertz. The international unit for measuring frequency, equivalent to the older unit of cycles per second. One megahertz (MHz) is one
million hertz. One gigahertz (GHz) is one billion hertz. The standard US electrical power frequency is 60 Hz, the AM broadcast radio
frequency band is 535–1605 kHz, the FM broadcast radio frequency band is 88–108 MHz, and wireless 802.11b/g LANs operate at 2.4
GHz.
IEEE Institute of Electrical and Electronics Engineers, New York, www.ieee.org. A membership organization that includes engineers,
scientists and students in electronics and allied fields. It has more than 300,000 members and is involved with setting standards for
computers and communications.
I/O Input/Output. The term used to describe any operation, program, or device that transfers data to or from a computer.
IP Internet Protocol (IP) is a set of rules used to send and receive messages across local networks and the Internet.
IP Address
A 32-bit number that identifies each sender or receiver of information that is sent across the Internet. An IP address has two parts:
an identifier of a particular network on the Internet and an identifier of the particular device (which can be a server or a workstation)
within that network.
ISM The industrial, scientific and medical (ISM) radio bands are portions of the radio spectrum reserved internationally for industrial,
scientific, and medical purposes other than telecommunications.
LAN Local Area Network (LAN) is a system of connecting PCs and other devices within the same physical proximity for sharing resources
such as an Internet connections, printers, files, and drives.
LQI Link quality indicator (LQI) is used in wireless networks to indicate how strong the communications link is. LQI is a computed value,
based on the received signal strength as well as the number of errors received.
Receive Sensitivity The minimum signal strength required to pick up a signal. Higher bandwidth connections usually have less receive sensitivity than lower
bandwidth connections.
Router
A device that forwards data from one WLAN or wired local area network to another.