Omron C-series manual Optical Remote I/O Systems, Units

	Optical Remote I/O Systems	Section 4-3
Example 3		As shown in Example 3, more than one Optical Host Link Unit can be connected
		in series using optical fiber cables. However, if any failure (power failure, discon-
		nection, etc.) occurs in one of the Units, all the subsequent Host Link Units will
		also cease to operate. This can be prevented by using Link Adapters such as the
		AL002-(P)E as shown below. These Link Adapters bypass any malfunctioning
		Host Link Unit, thereby allowing the rest of the system to operate normally. In
		other words, even if a power failure occurs in a Host Link Unit connected to a
		branch line of a Link Adapter, signals are still transmitted to the other Host Link
		Units.

Host computer .

RS-422 or RS-232C

Link Adapter

AL004-(P)E

Optical fiber (APF/PCF)
	Link Adapter	Link Adapter
	AL002-(P)E	AL002-(P)E

Link Adapter	Link Adapter
AL002-(P)E	AL002-(P)E

Optical fiber (APF/PCF)

C-Series PC

with

Optical Host

Link Unit

C-Series PC

with

Optical Host

Link Unit

C-Series PC

with

Optical Host

Link Unit

C-Series PC

with

Optical Host

Link Unit

C-Series PC

with

Optical Host

Link Unit

4-3 Optical Remote I/O Systems
Example 1	Example 1: In an Optical System, Units can be connected in series. However, if
	any failure (power failure, disconnection, etc.) occurs in one of the Units, all of

the subsequent Units will also cease to operate. This can be prevented by using Link Adapters such as the AL002-(P)E as shown below. These Link Adapters bypass any malfunctioning Unit connected to a branch line, thereby allowing the rest of the system to operate normally.

Link Adapter

AL002-(P)E

Link Adapter

AL002-(P)E

CPU Rack with Optical Master

Optical Link Rack

C120 CPU Rack

Optical Slave Rack

Optical fiber (APF/PCF)

C120 I/O Link Rack

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