Method for on-line calibration of low accuracy voltage sensor through communication bus

1. A method for calibrating voltage sensors in a switchboard, said switchboard comprising a circuit breaker, a voltage transformer at busbar level, a first voltage sensor, a second voltage sensor on one of two sides of the circuit breaker, a communication bus and a first electronic device, characterized by the following steps:

i. performing a measurement using said first voltage sensor;

ii. transmitting an information derived from said measurement to said first electronic device, through said communication bus; and

iii. using said information to calibrate said second voltage sensor.

2. A method according to claim 1 , characterized in that said first voltage sensor is a voltage transformer.

3. A method according to claim 1 , characterized in that said second voltage sensor is a capacitive sensor.

4. A method according to claim 1 , characterized in that said second voltage sensor is on the load side of said circuit breaker.

5. A method according to claim 1 , characterized in that first said electronic device is on-board said circuit breaker.

6. A method according to claim 1 , characterized in that said switchboard further comprises a plurality of electronic devices and a plurality of circuit breakers.

7. A method according to claim 6 , characterized in tat said information derived from said measurement is transmitted from said first electronic device to any of said plurality of electronic devices.

8. A method according to claim 7 , characterized in that at least a part of said plurality of electronic devices is on-board of at least a part of said plurality of circuit breakers.

9. A method of claim 1 , wherein the two sides of the circuit breaker are incoming and outgoing.