Terrasat IBUC 3, Operation Manual

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IBUC
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3 G
Operations Manual: Transmit Redundant Systems
Engineered to Endure
Category A
At the wall outlets (and more than 30 ft 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 current capability.
Category B
At the distribution panel, equipment can experience the 100 kHz ring wave but with
500 ampere current capability and a unidirectional impulse up 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 3000 amperes rising to peak in 8 ? s and decaying to half value in
20μs.
To ensure uninterrupted service, Terrasat recommends the use of a line conditioner
and/or UPS based on the expected AC power at the site.
Site-Related Problems
VSAT antennas are often fitted on top of buildings. Avoid close proximity to elevator
motors, etc. Also ensure that the satellite signal path is free and clear of obstructions.
M&C Checks
When troubleshooting redundant systems, the first level of troubleshooting should be
to check the status through the M&C ports. Alarms and an alarm history are available.
Refer to this chapter for specific information when using the RS232, RS485, Ethernet,
or hand-held terminal ports.
Power Supply Checks
For DC-powered IBUCs, before starting RF troubleshooting first verify that the proper
voltages are being supplied to the Tx Redundant System. Input DC Voltage and
current consumption data are available from the M&C. Verify that values are within
limits. If M&C is not available, use a multimeter to verify that the appropriate voltages
(24 VDC or 48 VDC) are present at the IBUC and Tx 1+1 Interface Module. The part
number label on the IBUCs contains the required voltage (24 VDC or 48 VDC).
Warm Standby Mode
In redundant operation, you can set the power amplifier into standby mode (a lower
power-consumption mode that is designed to reduce energy usage when enabled).
Depending on the model, the standby unit will only consume 20 watts to 100 watts.
When enabled, the standby unit will be muted (its output power turned Off) until the
switch to it occurs. Warm standby mode is available only when the A: side unit is the
primary (or protected) unit and the B: side unit is the standby unit. When the A: side
unit has been repaired, user intervention is required to place it back in redundancy
mode.