Teledyne HPAC-2005, Руководство по эксплуатации

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3 RU SSPA Chassis Operations Manual 205356 REV T 85
4.2.3 Auto Versus Manual Switching Mode
Normal operation mode for a 1:1 redundant configuration is “Auto”. This mode provides
automatic detection of SSPA faults and switchover to the operational SSPA. The sys-
tem is also protected from operator errors; selecting a faulted SSPA is not allowed. In
situations when system maintenance must be performed, “Manual” mode should be
used. In “Manual” mode, the operator can select the on-line and standby SSPA by
pressing the “Unit1” key. The system will not provide automatic switchover from a fault-
ed SSPA, but rather will keep the selected SSPA online, regardless of its state.
Note
: In order to function normally, both SSPAs in the system must uti-
lize the same switching mode.
4.2.4 Physically Rotating Transfer Switch
It is possible to physically rotate the shaft on the transfer switch to change the online
and standby amplifiers positions. This can be done either in manual or automatic
mode. When the switch is physically rotated in automatic mode the online SSPA will
attempt to return the switch to its previous position. The SSPA will make two attempts
to return the switch before accepting the new position.
4.2.5 Switchover Muting
The following option was introduced into the SSPA control setup to overcome a
problem with microwave arcing, which may potentially damage a switching component
if the switching RF power exceeds 400 Watts. This particular problem becomes a
critical issue if coaxial RF pass switches are used.
In general, all Teledyne Paradise Datacom SSPAs are well protected against high
reflected power conditions, which may take place during output microwave switchover.
However, waveguide or coaxial switches will develop an internal electrical arc during
switchover if the output power is significant. Such conditions will not lead to instant
failure, but over time may diminish some critical RF switch characteristics.
If this option is activated, the system ability to output RF power will be bonded to the
switch position sensing circuitry. Such circuitry consists of the following components:
SSPA electronic switch position detector; wiring harness between SSPA and RF
switch; RF switch position sensors. Failure of any of these components will lead to a
break in transmission. The factory strongly recommends to NOT turn on this option un-
less absolutely necessary.
To enable switchover muting from the SSPA Front Panel:
1. Press the
Main Menu
key;
2. Select
4.Flt.Setup
and press the
Enter
key;
3. Select
3.RF Switch
and press the
Enter
key;
4. Select
4.MutedSwitch
and press the
Enter
key.