EVM430-I2040S: Single Phase and DC Embedded Metering (Power Monitor) Using MSP430I2040

aswanth mohanan

Part Number: EVM430-I2040S

In ac input side the neutral is connected with AGND . So whether it is a good practice to connect both neutral and agnd.

over 2 years ago

0 Luke Ledbetter over 2 years ago

TI__Mastermind 23790 points

Hello,

The neutral is connected to AGND here so that the measurements are based off neutral, this also helps prevent tampering in readings. If the neutral gets disconnected then the voltage can't be measured.

Regards,

Luke

0 aswanth mohanan over 2 years ago in reply to Luke Ledbetter

Prodigy 10 points

Thanks for the reply. Whether it is good to directly giving to microcontroller without isolation?

0 Luke Ledbetter over 2 years ago in reply to aswanth mohanan

TI__Mastermind 23790 points

Hi Aswanth,

Are you asking for the EVM itself or with general designs?

The EVM uses an AC/DC converter to power the 3.3v VCC and utilizes isolation for the UART. See Figure 10-1: EVM Schematic in the Single Phase and DC Embedded Metering Power Using MSP430I2040. The debugger header does not have isolation, so it is highly recommended to program and debug before inputting the AC signal.

The Sigma Delta ADC input will be fine as long as the inputs don't go over the allowed range.

Regards,

Luke

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EVM430-I2040S: Single Phase and DC Embedded Metering (Power Monitor) Using MSP430I2040