Stopping Flow; Modifying Gradient And Event Tables - Waters 600e User Manual

When you press Hold:
• Gradient clock stops
• Run-time clock stops
2. To continue system operation from the point at which you suspended it, press the
Resume Run screen key. The gradient and run-time clocks continue from where
they stopped.

11.4.3 Stopping Flow

You generally use the Stop Flow screen key at the end of an analysis. However, you can
also use it to temporarily shut down your pump (for example, to adjust a fraction collector)
or to function as an emergency shutdown.
The Stop Flow function also suspends the method table, but does not stop the run-time
clock. The current event and detector tables continue to execute. However, pressing Stop
Flow causes switch S4 to default to the Off position. This action provides an additional
level of control for non-IEEE devices.
Note: The receipt of the Stop Flow signal (at the 600 controller's Stop Flow rear panel
terminal) suspends the controller's run, gradient, and event clocks. The three clocks
resume operation when the Stop Flow signal terminates.
To stop flow:
1. Press the Stop Flow screen key. The system displays the Stop Flow key in reverse
video and changes the Start Run screen key to Resume Run.
When you press Stop Flow:
• Flow rate is set to zero
• Gradient clock stops
• Run-time clock continues
2. To continue running the gradient, press the Resume Run screen key. The pump
ramps up to the rate at which it was running just before you pressed Stop Flow, and
the gradient continues. Note that this ramping affects any current analysis.

11.4.4 Modifying Gradient and Event Tables

While an analysis is in progress, you can modify any existing table except the one
currently in process.
198 Running Gradients