Total manometric head

13. Total manometric head is the difference in pressure (in metres) between the pump’s inlet and outlet points. This value is always higher than the actual difference in elevation between these two points; when pumping is going on, the pump needs also to overcome friction losses occurring as the water flows through the intake and outlet pipes. Appropriate tables and graphs are used to calculate “unit” friction losses; for this purpose, precise altimetric and planimetric plans containing pipeline layouts provide the best and most complete information

Смысл: показатели (величины) полной (общей) манометрической высоты (в метрах) для насосов с однофазными электродвигателями следует принимать на 10% меньше аналогичных показателей, указанных в таблице для насосов с трехфазными электродвигателями ...