Terrasat Rx 1+1, Operation Manual

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Fault Isolation
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6-3
Category A
– At the wall outlets (and more than 30 ft [9 m] from a distribution
panel) the typical noise is a 0.5 µs rise time up to 6 kV peak open circuit voltage,
100 kHz ring wave with 200 ampere short circuit capability.
Category B
– At the distribution pane, one can experience the 100 kHz ring wave
listed previously but with 500 ampere current capability and a unidirectional
impulse of to 6 kV potential rising in 1.2 µs and decaying to half voltage in 50 µs.
Accompanying this can be a short circuit current up to 3 000 amperes rising to
peak in 8 µs and decaying to half value in 20 µs.
To ensure uninterrupted service, Terrasat recommends using a line conditioner or
uninterruptible power source (UPS) based on the expected AC power at the site.
Site-Related Problems
VSAT antennas are often fitted at the top of buildings. Avoid close proximity to
elevator motors, etc. Ensure that the antenna has a clear path to the satellite. Ensure
that all cabling to the terminal is protected and has adequate slack.
M&C Checks
When troubleshooting the Rx 1+1 system, the first level of troubleshooting should be
to check the status through the M&C port. Alarms and an alarm history log are
available. See
Chapter 5, Monitor and Control Features and Functions for specific
information about using the RS232, RS485, Ethernet, or hand-held terminal ports.
Common Problems
The following problems or occurrences have been noted during normal
troubleshooting:
• Weather may cause interference in receive mode.
• The distant end may have weather that lowers their transmission power levels.
• The distant end may have lowered transmission power levels.
Damaged Cables
RF coaxial cable damaged due to improper handling (such as contact damage due to
improper mating; cable insulation that is damaged, crushed, cut, or charred; cables that
were not discharged prior to mating; or conductors that are nicked, gouged, damaged,
or severed) may impair system performance and reliability. Do not attempt to repair
broken or damaged coaxial cables unless absolutely necessary. Replace the cable
whenever possible.
Damaged cabling and incorrectly tightened connectors can leak RF energy which may
lead to excessive levels in the immediate vicinity.