3-18 D60 Line Distance Relay GE Multilin3.2 WIRING 3 HARDWARE3Figure 3ñ18: RS485 SERIAL CONNECTIONc) 10BASE-F FIBER OPTIC PORTENSURE THE DUST COVERS ARE INSTALLED WHEN THE FIBER IS NOT IN USE. DIRTY OR SCRATCHEDCONNECTORS CAN LEAD TO HIGH LOSSES ON A FIBER LINK.OBSERVING ANY FIBER TRANSMITTER OUTPUT MAY CAUSE INJURY TO THE EYE.The fiber optic communication ports allow for fast and efficient communications between relays at 10 Mbps. Optical fibermay be connected to the relay supporting a wavelength of 820 nanometers in multimode. Optical fiber is only available forCPU types 9G and 9H. The 9H CPU has a 10BaseF transmitter and receiver for optical fiber communications and a secondpair of identical optical fiber transmitter and receiver for redundancy.The optical fiber sizes supported include 50/125 μm, 62.5/125 μm and 100/140 μm. The fiber optic port is designed suchthat the response times will not vary for any core that is 100 μm or less in diameter. For optical power budgeting, splices arerequired every 1 km for the transmitter/receiver pair (the ST type connector contributes for a connector loss of 0.2 dB).When splicing optical fibers, the diameter and numerical aperture of each fiber must be the same. In order to engage or dis-engage the ST type connector, only a quarter turn of the coupling is required.CAUTIONCAUTION
