Networking Basic for PLC Engineer

In the world of computers, networking id the theory of connecting 2 or more computing devices together for the purpose of sharing important data. Networks are built with mix of hardware & software.

Basically Networks are categories into

Peer to Peer Networks
Client Server Networks

IEEE has developed different communication standards which are summarized in following table.

IEEE 802 Standards

Network Cabling

Cabling is medium through which information usually moves from one network device to another. There are several types of cables used in networks.

Some Guidelines for Installing Cables

When running cable , it is best to follow few basic rules:

Always use more cable than you need. Leave plenty of slack
Test every part of a network as you install it. Even if it is a brand new, it may have problems that will be difficult to isolate later.
Stay at least 3 feet away from fluorescent light boxes and other sources of electrical interference.
If it is necessary to run cables across the floor , cover the cable with cable protectors.
Label both ends of each cable
Use cable ties (not tape) to keep cables in the same location together.

Widely used Industrial Automation Networks

Wireless LAN

Not all networks are connected with cabling; some networks are wireless. Wireless LANs use high frequency radio signals.

What is Wi-Fi?

Short form of “Wireless Fidelity “.A term for certain types of wireless local area networks (WLAN) that use specification confirming to IEEE 802.11 or a limited range wireless networking protocol based on the 802.11 family of standards; uses spectrum in the 2.4 GHz range to exchange data at broadband speeds.

Wi-Fi has gained acceptance in many environments as an alternative to a wired LAN Many airports, hotels offers public access to Wi-Fi networks.

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Digital Fan Regulator Circuit Diagram

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