Specifications

SQ: 1-9
RS3: Service Quick Reference Guide
Troubleshooting
Troubleshooting Twinax PeerWay Cables
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To diagnose a twinax PeerWay cable problem:
1. Check all twinax cable connections for proper seating on the Tap
Boxes.
2. Check that both ends of the PeerWay are properly terminated.
3. Check for multiple grounds. Only one Tap Box on each PeerWay
(A and B) can have the jumper in the “SHIELD” position.
4. Check to make s ure that all twinax cable connectors are isolated
from ground.
5. Remove the “T” connector from the Tap Box, keeping the two
twinax cables connected to the “T” connector.
NOTE: The “Force Margin” field on the Peerway Overview screen should
show “None”.
Use an ohmmeter to measure the following resistances:
a. Between 1 and 2: 50 ohms nominal (acceptable range: 45 to
70 ohms)
b. Between 1 and shield: resistance greater than 1 megohm
c. Between 2 and shield: resistance greater than 1 megohm.
If the resistance between 1 and 2 is 100 ohms or greater (or in
extended length cable, 124 ohms or greater), there is a break
in one of the twinax cable s egments. Disconnect the two
twinax cables from the “T” and measure between 1 and 2 of
both c able ends. The reading should be between 100 and
140 ohms. Follow the faulty cable back until the open is
located. Terminations at both ends should read 100 or 124
ohms.
If the resistance between 1 and shield or between 2 and
shield measures less then 1 megohm, this indicates a short
between one of the lines and the s hield. Disconnect the two
twinax cables from the “T” connector and measure each cable
to find the faulty end. Continue following the cable segments
until the fault is found.