Design specifications and considerations 1. The voltage at any final load may not deviate from the supply voltage by more tha 6% in the case of single-phase circuits 8% in the case of three-phase circuits 2. The maximum wattage of any socket circuit shall not exceed a value of 4 kW 3. The maximum wattage of any lighting circuit shall not exceed a value of 1.4 kW 4. All sockets outlets, except those supplying critical loads, shall be connected to earth leakage 5. All light fittings with contactable metal structures should be connected to earth leakage 6. Dedicated socket outlets should be connected to individual circuit breakers 7. The nominal rating of a circuit breaker supplying a motor shall not exceed a value of 130 % of the full load current of the motor.