Meter hardware

AN2288

14/29

Figure 9.

Gain switching circuit

4.1.7

EEPROM block

After power up, the accumulated kWh data, tampering information and calibration

parameters are read by the microcontroller and stored in the form of RAM variables. When

the meter is tampered, the tampering information (meter is tampered and tampered

channel) will be stored in the EEPROM immediately. When power goes off, the accumulated

kWh data will be stored in the EEPROM.

+

-

3.75V

R9

R8

From Analog switch

x 2

+

-

3.75V

R10

R7

From Analog switch

x 8

+

-

3.75V

R11

R14

From Analog switch

x32 or

x128

C39

Analog input to ADC

Analog input to ADC

Analog input to ADC

Controlled by MCU

R12

R13