User Manual

SGD-SB2025NT-TUM, Part 1
Jan 12 Page 22 GENERAL DESCRIPTION
4.1.1.1 LED Indicators
The functions of the front panel LEDs are explained in Table 6 below. Each LED indicates the
status of the SB2025NT in real time.
Table 6. SB2025NT LED Functions.
LED FUNCTION
PWR Indicates the power supply voltage is within software selectable limits.
Rx The Rx is receiving a signal or the receiver’s squelch is open.
Tx The Tx is transmitting RF power.
ALARM A pre-arranged alarm condition exists.
M
This is a tri-colour status LED that indicates the condition of the TM module if
fitted. The conditions that can be indicated are detailed in Table 7 below.
N
This is a tri-colour status LED that indicates the condition of the NI module. The
conditions that can be indicated are detailed in Table 8 below.
4.1.1.2 Traffic Manager LED Indicator
The conditions indicated by the state and colour of the tri-colour status LED for a TM Module are
listed below in Table 7.
Table 7. TM Status Indicator.
Colour State Condition
Green Steady Normal Operation
Yellow Flashing (approx 1 Hz) Power ON and booting, for about 40 s from Power ON.
Green Flashing (approx 1 Hz)
Traffic Manager firmware starting (about 40 s after a Power
ON or immediately after a firmware change)
Red Steady Unacknowledged system alarm
Yellow Steady Acknowledged system alarm still present
4.1.1.3 Network Interface LED Indicator
When power is first applied to the NI, the LED will not show the valid status of the module for
several seconds. The unit becomes operational in under 5 seconds, although it will take longer for
the Phase Locked Loop (PLL) to become locked when absolute synchronisation is achieved
assuming that the 1PPS timing signal is present at Power ON. If a GPS Rx is being powered by
the Solar unit, the GPS acquisition time will need to be included.
The conditions indicated by the state and colour of the tri-colour LED for a NI Module are listed
overleaf in Table 8.