The jacks commonly used in patch panels in the U.S. conform to Western Electric standard dimensions. The number of insertion cycles a jack can endure should be rated in the tens of thousands. The factors affecting the life and reliablility of a jack include contact wear and failure of the termination switch. Descirable features include the following:
● Contacts fully isolated from the panel.
● Sealed metal housing to keep out contaminants and provide EMI protection.
● Easy replacement from the front of the panel.
● Low VSWR (below 600 MHz)
● High signal isolation (40 dB)
● 75 Ω characteristic impedance.
● Wide designation strips, making it easier to label the field and to allow more flexibility in selecting names that will fit on the lables.
If a patch cable is inserted in the signal path of a timed video system, it will delay the signal by an amount determined by its length and physical properties. The patch thereby alters the timing of the signal path. This can be avoided by using phase-matched normal-through fiber patch panels. The design of these patch panels anticipates the delay caused by a fixed length of patch cable by including that length in the loop-through circuit.
With phase-matched panels, the normaling connection in each connector module includes a length of cable that provides a fixed delay through the panel, usually 3 ft (0.914m). If a patch cord of the same length as the internal cable is used to make connections between patch points, the delay will be the same as that of the normal-through panel. When a fiber optic patch cord is plugged in, it is substituted for the loop cable through the swiching mechanism normally used in normalled patch connectors. Thus, critical timing relationships can be maintained.
In a normal uncompensated patch panel, when a cable is used to patch between two points on the panel, the length of the patch cord is added to that of the cables connected to the patch. The additional cable length delays the signal by approximately 1.52 ns/ft (5 ns/m). To avoid the delays associated with conventional patch panels, phase-matched normal-through video patch panels should be used.
If phase-matched patch panels are used, all of the patch cord must be the same length as the delay built into the patch panel. Obviously, if all of the patch cords must be the same short length for the phase-matched panel, it would not be possible to patch between panels that are separated by a longer distance than the cord can reach. This limitation should be considered when laying out patch panels in a fiber enclosure.
Color-coded cables can be specified. When different-length patch cords are specified, different colors can be used to distinguish one length from another for better cable management.
Fiberstore specializes in fiber optic patch cable assemblies and fiber optic network devices manufacturing since 1995, we are known as the fiber optic cable manufacturer for the excellent products quality, competitive prices, fast delivery and good service. Our fiber optic cables are available with combinations of LC, SC, ST, FC, and MTRJ connectors and come in 1, 2, 3, 5, and 10 meter lengths (and OM3 cables up to 30 meters). We offer LC fiber optic cable, SC fiber optic patch cables, SC LC fiber patch cable ect. We not only offer OEM fiber optic patch cord assemblies to some world leading companies in this industry, but also cooperate with many other companies from all over the world and support these partners to win in the market.