Cisco Systems 1500 manual Connecting Optical Isolators, Installation Notes, 5-14

Chapter 5 Connecting Optical Cables

Connecting Optical Isolators

Caution When connecting Cisco Metro 1500 series systems, you must adhere to the minimum remote link budget, as called out in Table A-9 on page A-15. If you do not adhere to this minimum budget, you might damage the receivers of the channel cards. This damage can only be repaired at the factory and is not covered by the warranty.

Connecting Optical Isolators

The Cisco Metro 1500 series optical isolator allows direct transmission from a WCM over a remote (or trunk) fiber. The optical isolator enables a WCM to bypass the multiplexer/demultiplexer (MUX/DMX) module in the system chassis. By connecting the WCM to the optical isolator through fiber jumpers, you can transmit directly over the remote fiber and obtain an additional 3 dB to 5 dB for use in your optical budget.

The optical isolator minimizes optical back reflection. Optical back reflection is common in fiber-based transmissions. Back reflection is a small amount of light that is reflected back towards the transmitting optical component. The optical isolator absorbs this reflected light so that the transmitting optical component operates with minimal interference.

Installation Notes

The optical isolator is connected directly to a jumper that extends from the remote connection of the WCM. The optical isolator sits between the WCM and the remote (or trunk) fiber. (See Figure 5-10.)

	Cisco Metro 1500 Series Hardware Installation Guide
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