STPM32 shunt connection

[KAsim]

Hello,

I am designing an e-meter based on the STPM32. I will be measuring current through a shunt resistor. According to the evaluation board gerbers, the shunt should be on the low side and connected to the Neutral line.

Is that correct? Should the PCB ground be connected to the Neutral as well?

Is it possible to connect it to the high side?

Thanks.

[Cristiana SCARAMEL · Accepted solution]

Hello @KAsim​,

the evaluation board can be connected to line voltage and current in several ways (for more details refer to user manual UM1748 section 2.2 at page 9). 

The shunt is at the same potential of voltage neutral faston and therefore it is at the same potential of the board GND.

When isolated power sources are used or phantom loads, this is not important.

In case of connection to the mains, this has to be taken into account since, according to the wire connected to the shunt, the board GND may be either at the 0 or 230 V potential.

Let me know if this solved your doubts.

[KAsim]

OK great, thank you for your help.