Omron CS1W-ETN21 operation manual Cascade Connections, Stack Connections, Hubs per stack

Network Installation Section 2-4

Hub Installation Environment Precautions

Hub Connection Methods

Note

•Do not lay the twisted-pair cable near devices that generate noise.

•Do not lay the twisted-pair cable in locations subject to high temperatures or high humidity.

•Do not lay the twisted-pair cable in locations subject to excessive dirt and dust or to oil mist or other contaminants.

•Do not install the hub near devices that generate noise.

•Do not install the hub in locations subject to high temperatures or high humidity.

•Do not install the hub in locations subject to excessive dirt and dust or to oil mist or other contaminants.

If more hub ports are required, they can be added by connecting more than one hub. There are two possible connection methods for hubs: Cascade and stacked.

Cascade Connections

•Connect two hubs to each other as follows: Connect an MDI port to an MDI-X port with a straight cable; connect two MDI ports with a cross cable; and connect two MDI-X ports with a cross cable.

It is very difficult to distinguish cross cables and straight cables by appear- ance. Incorrect cables will cause communications to fail. We recommend using cascade connections with straight cables whenever possible.

•With cascade connections, up to 5 segments can be connected using up to 4 repeaters (i.e., 4 hubs).

MDI ports		Straight cable
MDI-X port	Hub
(cross)		Cross cable
Hub	Hub	Hub

Stack Connections	• Connect the hubs using special cables or special racks.
	• Normally there is no limit to the number of hubs in a stack, and each stack
	is treated as one hub. Some hubs, however, are limited in the number of
	hubs per stack.
			Hub
		Four stackable hubs		Two stackable hubs
			Stack cable		Stack cable

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