Batch Controller - Model 515-CB01

The 515 CB01 application is a blending controller measuring the blending flow in a main and process line using frequency flow inputs.
The blending controller can operate in the Pre-set, On-Off (manual) and Release mode during operation. The “release” mode allows for easier tuning of the control loop.

The main and process flows are used to determine the net volume flow. The operator can view the ratio of totals as well as the ratio of flowrates.

The control of the process flow is via a digital control valve. The flowrate deadband and control responsiveness can be adjusted to reduce wear on valves.

Calculations

Blend Point Location:

The controller caters for blending points before and after the main flowmeter. The process flow is a ratio of the net (combined) flow (o-80% range).

Pflow
Ratio% = —————- × 100
Netflow

During the delivery the ratio setpoint is modified to cater for the flush volume:

Pre-set
SP ratio (mod.) = P ratio —————-
Pre-set – Flush