Agilent Technologies 1100 Series Service Manual page 213

Introduction to the Nano Pump 5
The stroke volume for the pump is set to AUTO mode. This means that the
stroke is optimized for the flow rate in use. A change to larger stroke volumes
is possible but not recommended.
When the pump is in the standard mode, the EMPV is fully closed. Total main
flow, up to 2500 µl/min, is directed to the LC system. Column flow
measurement/control is disabled. This mode is for non-capillary LC
applications.
In the micro mode, the flow sensor measures and controls column flow in the
range of 0.1 µl/min to 4 µl/min. Flow measurement is based on the principle of
mass flow temperature sensitivity. The flow sensor consists of a heated tube
with two temperature sensors. As the mobile phase passes through the heated
tube, the temperature characteristic distributed over the two temperature
sensors is evaluated. From the temperature characteristic, flow rate accuracy
is determined. The flow sensor measurement is calibrated for specific mobile
phases, which are user-selectable.
1100 Series Nano Pump Service Manual 201