'Meters' are intended as diagnostic instruments. They allow displaying signals both in SI-units or in 'pu'. Use them only when and where needed. Otherwise use 'Sensors'.
Output variables:
p power term_p to term_n v difference voltage 'plus' - 'minus' v0 average voltage ('plus' + 'minus')/2 i current term_p to term_n, ('plus' - 'minus')/2i0 sum current term_p to term_n, 'plus' + 'minus'