Adcom A723, A720 manual More about the LED tool

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CHAPTER 3

Using the RTU

This completes the installation of your addIT RTU. If one of the I/O connectors is left unused, use the cap specially provided to protect it against moisture and dust. Be sure to make a note of the follow- ing information because you’ll need it when you configure the device in the software:

•Serial number for each RTU

•Type of sensors connected to each RTU

More about the LED tool

The LED tool allows you to rapidly check the status of an addIT RTU. After you insert the LED tool into the POWER connector, the unit waits up to two seconds and then sends a broadcast frame. If a nearby listening station or receiver decodes the frame, it will answer back—this may take up to 10 seconds. When an answer is received, the LED tool lights up for about 4 seconds. After another few seconds, the LED lights up one or more times, depending on the number of stations/receivers that answered to its broadcast frame.

Note: addIT RTUs do not respond to a broadcast frame, only remote stations (A730MD) and base stations (A730SD or A720B).

In addition, the LED always blinks briefly at 0.5 second intervals to indicate that the unit is alive and the internal battery has enough energy to operate. If the blinking interval lengthens to 2 seconds, the battery has become undercharged (that is, under 5.6 volts but over 5.2 volts)—this is called the misery state. In this state, an addIT RTU reduces its activities to a minimum. The radio unit is switched off, the sensor sampling ceases, and no data is stored in the internal memory. Only the internal real-time clock is maintained and the power management functions are performed.

If the battery level drops below 5.2 volts, the system switches com- pletely off, effectively decoupling itself from the battery in order to protect it. In this case the LED tool stays permanently off. An addIT RTU in such a situation will restart only after connecting it to an external power supply (even a solar panel under low light condi- tions).

Note: New addIT RTUs are delivered with their internal batteries unformatted, meaning they are completely discharged, and you should install them only on sunny days. The battery will