TRB255 LEDs

This wiki page contains information about TRB255 gateway LEDs and their actions.

Power LED

The power LED is located on the bottom left corner of the front panel, near the power connector:

It can perform two different actions:

Action	Description
LED turned ON	Gateway is powered up
LED turned OFF	Gateway is not power up

Ethernet port LEDs

The Ethernet port LEDs are located on the gateway front panel, in both upper corners on Ethernet port:

Since TRB255 gateway supports Fast ethernet speeds, green LED is not used and only orange LED represents information about ethernet connection activity:

Action	Description
LED turned ON	Operating as a 10/100 Mbps connection
LED turned OFF	No link established
LED blinking	Connection established and there is activity (data being transferred)
LED blinking fast simultaneously with connection and signal strength LEDs	Router is in the bootloader menu state*

* The bootloader menu is a special router state from which certain upgrades can be performed. For more information on the bootloader menu, click here

Connection status LED

The connection status LEDs are located on left side of the back panel:

Action	Description
2G, NB and M1 LEDs are blinking at the same time	No SIM or bad PIN
2G, NB and M1 LEDs light up and down in sequence	The device is attempting to connect to a mobile network operator
2G/NB/M1 LED blinking	Gateway connected to 2G/NB/M1, no data session established
2G/NB/M1 LED blinking rapidly	Gateway connected to 2G/NB/M1 and data is being transferred
2G/NB/M1 LED turned ON	Gateway connected to 2G/NB/M1 with data session

* NB and M1 is Narrowband IoT (NB-IoT) and LTE Cat M1 communications technologies respectively

Signal strength LEDs

The signal strength LEDs are located on the right side of the back panel:

Each lit up LED represents a different value of the gateways current signal strength in RSSi:

No. of lit up LEDs	Signal strength value
0	≤ -111 dBm
1	-110 dBm to -82 dBm
2	-81 dBm to -52 dBm
3	≥ -51 dBm

The signal strength LEDs can also be used as a time indicator for holding the reset button. When you press and hold the reset button, if there is a User's default configuration configured on the device, you have to hold it pressed for 6 seconds (by default) to initiate a User's default configuration reset and 12 seconds (by default) to initiate a Factory reset. Otherwise, it is only necessary to hold the reset button for 6 seconds to trigger a Factory reset. If the button was held down longer than 20 seconds (by default) no action will be taken.

While holding the reset button each lit up signal strength LED indicate that a period of two seconds has passed. In case with TRB255, when all 3 signal strength LEDs are lit up, they represent that 6 (LED number multiplied by 2) seconds have passed since you pressed down on the reset button.

After releasing the button at one of the reset periods, all 3 LEDs will start blinking every 1 second. This signifies that the router has begun the reset.