Electricity sensor to check if a lamp is on

Hello friends :smiley: I want to detect if a lamp in my house is ON or is OFF, but this lamp is not connected in my Seeeduino. The only way to turn it ON/OFF is using a switch on the wall. Also, I dont want to use light sensors because are many lamps and I need to know each one if is ON or OFF (different switches). Iā€™m trying to use the electricity sensor but it shows me the same values, even the lamp is ON or OFF. It can be used to discover this? Is there any other better way to discover this?

Sorry for my english, is not my primary language. Thanks in advance!