Terrasat IBUC 2, Operation Manual

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Cyber Hardened IBUC
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, IBUC
2 G
, IBUC
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, IBUC
G
Operations Manual: Troubleshooting
Engineered to Endure
Whatever the origin of the transients, they can be classified into two simple categories:
• Common Mode
Noise voltage that appears equally and in phase from each signal conductor to
ground. (The term “common” refers to the fact that identical noise appears on both
the active and neutral wires.) Common-mode noise poses a threat because the
noise attempts to dissipate its energy from neutral to ground or from active to
ground.
• Normal Mode
Noise potential between the power line conductors. It adds to and subtracts from
the power line sinusoidal voltage wave and is sometimes referred to as
differential - mode noise or transverse - mode noise. Normal-mode noise attempts to
dissipate its energy along any path from line to neutral. If the normal-mode noise
has sufficient voltage (or energy), damage can occur.
Category A
At the wall outlets (and more than 30 ft. [9 m] from a distribution panel), the typical
noise is a 0.5

s rise time up to 6 kV peak open circuit voltage, 100 kHz ring wave
with 200 ampere short circuit current capability.
Category B
At the distribution panel, one can experience the 100 kHz ring wave listed previously
but with 500 ampere current capability and a unidirectional impulse up to 6 kV
potential rising in 1.2  s and decaying to half voltage in 50  s. Accompanying this can
be a short circuit current up to 3000 amperes rising to peak in 8

s and decaying to
half value in 20  s.
To ensure uninterrupted service, Terrasat recommends using a line conditioner or
uninterruptible power supply (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, and such. Ensure that the satellite signal path is free and clear of
obstructions.
M&C Checks
When troubleshooting the IBUC, the first level of troubleshooting should be to check
the status through the M&C port. Events and an event history log are available with
the IBUC M&C. For specific information about using the RS232 or Ethernet ports, see
Chapter 5, Monitor and Control Features .