What is the objection to have lamps connected in series?
- If breaks occurs in any part of the circuit, no current will flow and the entire circuit become useless ( whole lamps will be off)
- A High Supply voltage is required if the lamps ( or other electrical devices) are to be connected in series.
For efficient operation, only those lamps or devices should be connected in series that have the same current rating. however, electrical devices (e.g., heater, toaster, grinder, lamp etc.) have different current ratings. obviously, they cannot be connected in series for efficient operation.