Hi VincentH,
Welcome to audiocircle and the RWA forum!
If you are going to be away for only a month, you can disconnect the charger from your 30.2 (if you feel more comfortable not having it plugged in). First, fully charge your 30.2. Then unplug your charger from your wall outlet AND the 30.2.
If you are not going to be using it for longer than that, it is probably better to leave the charger plugged in. You can disconnect all your equipment form the 30.2 and leave the charger plugged into the 30.2 and wall outlet. The charger will keep the batteries "float charged," which is the best for them as SLA batteries like to always be in the fully charged state for longest life.
Best regards,
Vinnie