PUMPS ARRANGED IN SERIES :-
WHEN TWO PUMPS ARE ARRANGED IN SERIES, THE TOTAL HEAD OF THE SYSTEM ADDS UP. SINCE EACH PUMP GENERATES A HEAD CORRESPONDING TO A QUANTITY Q HENCE, IF H1 IS HEAD PRODUCED BY PUMP 1 AND H2 IS THE HEAD PRODUCED BY PUMP 2, THEN THE TOTAL HEAD PRODUCED BY BOTH THE PUMP IN SERIES WILL BE
H=H1+H2
PUMPS IN PARALLEL :-
WHEN TWO PUMPS ARE ARRANGED IN PARALLEL, THE FLOW RATE ADDS UP FOR A COMMON HEAD. TOTAL QUANTITY ADDS UP TO
Q=Q1+Q2
THE HEAD AND FLOW RATE FOR THE TWO CASES DEPENDS ON THE SYSTEM CURVE