2.7 Status Indicators

There is a panel with five LEDs on the gateway upper cover. The Power indicator signals that the gateway as a whole is in operation. The other LEDs, marked CH 1 through CH 4, indicate the status of each module.

Power Indicator

Basic diagnostic tests are performed automatically whenever the gateway is connected to the supply voltage. Each test step is signalled by a specific colour combination of the LEDs. The testing process is usually shorter than 0.5 sec and so it looks like a quick sequence of LED flashes at first sight. If, however, a test step fails, the indicator combination related to the failed test remains on. This provides a convenient troubleshooting tool to the technical support personnel.

After all hardware tests have been completed successfully, the operating system kernel is loaded. During the process, all module indicators are off and the blue continuous Power light flashes in approximately 1–second intervals.

When the operating system kernel has been loaded, the blue Power indicator keeps shining continuously.

In exceptional cases, when a fatal software error occurs and the gateway stops working, the Power indicator starts flashing quickly. All you can do is disconnect the gateway from the power supply for a few seconds and then restart it. 

Power Indicator (blue)

No light

The system is not working.


The system kernel is being loaded.

Continuous light

The system is working.

Quick flashing

Fatal error.

GSM Indicators

The CH 1 – CH 4 indicators indicate the signal status of the respective GSM module. After connection to the power supply, the VoIP gateway application starts running within two minutes. During that time, the installed GSM modules and SIM cards are detected. If not detected, the respective indicator remains off.

If detected, the module and SIM card initialisation process is commenced. If the process is unsuccessful, the LED goes red. If the indicator turns orange, it means that the module has not logged in to any GSM network.

If the LED is off, you can make calls and send SMS via the respective module.

The respective module LED flashes green quickly during call set–up or data connection in the case of UMTS module. When the connection has been established successfully, the indicator remains green during the whole call.

GSM Indicators

No light

The module is ready.

Red light

SIM card initialisation in progress or no SIM card is in the drawer.

Yellow/Orange light

The SIM is not logged–in to any GSM network.

Quick green blinking

A call is being set up (dialled).
Data connection active.

Green light

A call is being made.