I am a beginner in Arduino and electronics but I want to pursue power monitoring inside the home to dig deeper on the technology. I conceptualized my project to have multiple room modules connected to a center hub.
For the real question, I imagine my individual room modules to have multiple ACS712 Current Sensor that are connected to multiple plugs/switches. I imagine that the module will sit on the middle of the power supply (from service provider) and the loads. The problem that I see is that due to placement, I need to put resistors to not fry up the board. However, the current will not be enough to power the load (I assume).
Are there any methods that I can use or revise on my current concept or this is not feasible at all?
The problem I see is a mass of wires running all over the room, connecting various modules.
If you consider connecting two different rooms, be aware that the hot wires, not the ground or common wires, will most likely have a voltage difference of 250 volts or more AC.
Rule: never connect AC powered devices that are in separate rooms.
DO NOT try to measure mains current with sensors connected in series with the wiring (such as ACS712) use current transformers (CTs) which are isolated from mains voltage. A 120 volt AC to ground is a hard shock! 230 volts can easily be lethal!
Check out OpenEnergyMonitor.
@ Paul_KD7HB has a good point. If you are in North America, with the 120/240 volt "split phase" system, one room could be fed from line1 and the other from line2, so 240 volts from line to line.