For 3P breaker used in single phase load with micrologic NSX 5E/6E, we recommend connecting the "Network Neutral line" on upstream pole 1 and the "Network Phase line" on upstream pole 3. (see picture below)
The micrologic ENVT voltage tap must be wired to upstream pole1 and declared with Ecoreach. The downstream pole 2 must be connected to the downstream pole 1 as well to read correct values on pole 2.