After day five I am hearing Noise from my inverter "Sukam Smily" I called them and as per service engineer it is normal and the sound will come. This sounf is due to capacitor. HELLO have u guys have ever heard about an inverter (electronic device) which gives noise. Last week I have given an written complaint to these guys and I got only one call and that guy says this sound is normal as this sound is of an capacitor, still he will come and since then no body is here to rectify.
It seems that these Sukam guys have started making capacitor in there own factory . As per my little knowledge capacitor do not make any noise had that been the case all the electronic devices have them. Go ahead for purchase if your house is near railway station and you are comfort with noise. Rest backup and charging is fine.