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Main Page > TRB Gateways > TRB256 > TRB256 Manual > TRB256 LEDs

This page contains information the different types of LEDs and their behaviour on a TRB256 device.

Power LED

The power LED is located on the bottom left corner of the front panel, just under the power connector.

Networking trb256 manual leds power led.png

It indicates whether the device is powered on or not.

State Description
LED turned on Device is powered on.
LED turned off Device is not powered on.

Ethernet port LEDs

The Ethernet port LEDs are located on the device's front panel, under each respective Ethernet port.

Networking trb256 manual leds ethernet leds.png

State Description
LED on Operating as a 10/100 Mbps connection.
LED off No link established.
LED blinking Connection established and there is activity on this port (data being transferred).

Mobile network type LEDs

The mobile network type LEDs are located on left side of the back panel:

Networking trb256 manual leds mobile network type leds.png

They display which type of Internet connection is currently active.

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 Searching mobile network operator
2G/NB/M1 LED blinking Gateway connected to 2G/NB/M1, no data session established
2G/NB/M1 LED turned ON Gateway connected to 2G/NB/M1 with data session
2G/NB/M1 LED blinking Gateway connected to 2G/NB/M1 and data is being transferred

Mobile signal strength indication LEDs

The mobile signal strength indication LEDs are located on left side of the back panel.

Networking trb256 manual leds mobile signal strength leds.png

The number of lit up LEDs represents a different mobile signal strength (RSSI) value in dBm.

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 Mobile 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 TRB256, when all 3 Mobile 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.