Black Box LZ1500A-R3, Руководство пользователя

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9
UTP AND THIN ETHERNET REPEATERS
If you have any questions about which protection devices to use, call
Black Box Technical Support at 724-746-5500.
3.2 UTP Repeaters Quick Start Installation
1. Install the repeaters in the wiring closet, near the central punch down
block or patch panel.
2. Repeaters can be placed on a shelf (attach adhesive feet), or wall-
mounted with Velcro strips (LZ1500A-R2, LZ1502A-R2, LZ1503A-R4)
or mounting brackets (LZ1504A).
3. Inspect existing telephone wire to locate the two end points of an
unused pair.
4. Measure the lengths of the phone wire that will connect the repeater
ports to be certain that the distance is less than 1500 ft (457.2 m). To
do so, short-circuit one end of the phone-wire pair and measure the
resistance between the two wires at the other end. Multiply the
resistance by 20 to find the length of the wire in feet. For example, a
reading of 54.6 ohms indicates roughly 1,100 feet of cable (54.6 x 20 =
1092). For a maximum of 1,500 ft., the resistance must measure 75
ohms or less. This formula works for standard 24 gauge phone wire.
5. Check that the wires are properly protected against hazardous voltages
(see Section 6.1).
6. Make patch cables with RJ-11 plugs. Wire the RJ-11 plugs using the two
center pins, 3 and 4. Connect them straight through, pin 3 to 3, pin 4
to 4 (do not reverse polarity).
7. Plug in the power supply and attach it to the repeater. The LEDs on
the repeater will alternate between red and green.
8. Attach patch cables to the repeater ports and phone block. When
repeaters have been interconnected, the LEDs will remain constant;
one Repeater will show a steady red LED, the other will show a steady
green LED.
9. Now connect your existing LAN to the repeater using the appropriate
ports, BNC or AUI.
NOTE
For safety, IEEE 802.3 10BASE2 Ethernet specifications call for each
segment to be connected at one point to an earth ground such as a cold
water pipe. To simplify your system’s installation, we have internally
connected the ports’ grounds in our repeaters together and recommend
that the earth ground connection be made from only one of the ports on
the repeater. Grounding one segment in this manner will properly
ground all the 10BASE2 segments connected to the repeater.