Hitachi ChromasterUltra Rs 6270 Instruction Manual page 58

2.2 Operating Principle and Functional Description
(d) Wash of the needle outer wall with the wash fluid1
The syringe aspirates one-half of the air volume (va/2)
while needle is moving to the rinse port.
Deliver the wash fluid1 via the wash pump to rinse the
needle outer wall.
Figure 2-15 Rinsing the Needle Outer Wall
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