Mute Control; Faults - Comtech EF Data LPOD Series Installation And Operation Manual

5.2.3 Mute Control

You may mute the LPOD via software or discrete control:
•
Software – Using the MUT=1 command will "software" mute the unit.
•
Discrete Control – When using the AUX=1 command, the LPOD will be muted until Pin 'S' (on the 'J6 | COM1' Discrete Control
Connector) is pulled to ground (Pin 'K'). At that time, the unit unmutes.
The Mute command provides over 60 dB of RF on/off isolation. However, the Mute command only turns off the first few low power stages
of the amplifier while the high power stages remain on. By allowing the higher power transistors to stay on, the LPOD remains in more
thermally stable state should the mute condition be removed.
If you wish to completely turn off the bias to the entire amplifier (perhaps to conserve energy in a redundancy system), both the MUT=1
and AMP=0 commands should be executed. For normal transmit operation, MUT=0 and AMP=1 are required.

5.2.4 Faults

The M&C system monitors certain key functions of the LPOD for proper operation. Should any of these parameters exceed predetermined
limits, the M&C system will declare a fault. The conditions that trigger a fault are:
•
Any power supply more than ± 10% outside its nominal value.
•
Fan less than 25% of maximum speed.
•
I2C internal bus communications fault.
•
Thermal Shutdown – A temperature fault is indicated if the unit is +>90°C. This creates a summary fault and will cause the unit to
mute itself and switch to the back-up unit (if in a redundancy system). However, the 10V supply to the FET transistors will remain
on until the unit reaches the thermal shutdown temperature of ≥ >95°C. For protection reasons, the unit will shut down the 10 V
supply to the power transistors at temperatures >95°C.
•
Firmware checksum error at power up.
•
FPGA done indicator error at power up.
•
*BUC unlocked.
•
Redundancy waveguide switch position fault (applies to redundancy mode operation only).
•
Redundancy inter-unit link fault (applies to redundancy mode operation only).
•
LNB current over limit.
Serial Interface Operation
Low Power Outdoor (LPOD) Amplifier/Block Up Converter (BUC)
5–2
Revision 15
MN-LPOD