Graseby 3000/500, Manual

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5 — 5
G r a s e b y M e d i c a l L t d .
5
3 0 0 0 / 3 1 0 0 a n d 5 0 0 / 5 0 5 S e r v i c e M a n u a l I s s u e A ( A p r i l 2 0 0 2 )
V o l u m e t r i c I n f u s i o n P u m p s
Due to the 20:1 gear reduction and half stepping, 1,920 pulses yield
one full revolution for rates of 499 mL/h and less. Each cam shaft
revolution and the resulting cycle of the pumping mechanism delivers
approximately 1.7 mL of fluid. Delivery of fluid to the patient is
smooth since each mL is delivered in approximately 1,130
increments. The 3100/505 pump is half stepped at all rates.
At rates of 500 mL/h and above, due to the gear ratio of 20:1 and
whole stepping the motor, each mL of fluid is delivered in
approximately 565 increments.