Flow Reduction; Flow Reduction When Column Switching; Flow Reduction For Pump Protection (G7161B Only) - Agilent Technologies InfinityLab LC Series User Manual

1 Introduction

Flow Reduction

Flow Reduction

Flow Reduction when Column Switching

In a pressure cluster hosted by a Preparative Binary Pump, the flow reduction
feature protects the instrument and column from pressure spikes caused by a
switching valve by reducing the flow rate before switching the valve.
The flow reduction sequence is as follows:
1 A valve switch command is issued by the user or method.
2 The flow rate is reduced to zero mL/min at the rate defined in the Flow ramp
3 When the flow rate reaches zero mL/min the pump sends a signal to the valve
4 The valve switches and sends a signal to the pump when it is at its new
5 The flow rate is increased to the current set point defined in the Flow ramp up
The time taken to complete the valve switch will be increased if lower flow ramp
NOTE
values are used.

Flow Reduction for Pump Protection (G7161B only)

The flow reduction feature protects the pump against running dry at high flow for
extended periods.
The protection mechanism is triggered if the flow rate is 150 mL/min or higher
and the pressure is below 20 bar for 1 min. The flow rate is then reduced to
50.00 mL/min, but the solvent composition remains unchanged. The status LED
on the pump is yellow while the flow reduction is in force. In the driver dashboard,
the status bar is yellow (Not Ready), and the tooltip of the status bar displays Flow
Limit. The extended module tile in the dashboard displays the source of the limit
as Protect.
To clear the flow reduction feature, either set the flow rate for the respective
channel to 50 mL/min or less, or turn the pump off.
Preparative Binary Pumps User Manual
down setting (default: 600 mL/min/min) of the active method.
that it is safe to switch.
position.
setting (default: 600 mL/min/min) of the active method.
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