Posted to News on 19th Nov 2007, 20:55
Three-term PID controller optimises two-stream blending
Jiskoot's new Inspec blender controller is a three-term PID controller that is cost-effective yet powerful and versatile for two-stream controlled rate or 'wildstream' blending and analyser trim applications.
Designed to optimise blending performance, it has a simple user interface with operator prompting and 'hot-keys' to display key parameters or alarms. The display has 12 configurable scrolling front display items including indicators that can be configured to show any variables during the blend process.
Twenty user-defined recipes can be configured and stored for instant recall and recipes may also be entered on demand. Batch delivery optimisation includes a self-tuning algorithm to learn the blender piping configuration and ensure accurate blended batch quality.
This instrument is a closed-loop ratio controller with a series of factory set or retro-activated options to enhance functionality for different system types and application complexities. These include blend trim control to optimise final product using an online analyser, direct auxiliary automated control option, external pump and valve control integration, batch quality calculations including viscosity and density, print option for batch-end reports, or logging data from up to eight parameters during batching, Modbus networking is available for full remote access operation, recipe storage and remote panels.
Blend flow can be operator-entered or the controller can automatically calculate the optimum blending rate to maximise throughput. It corrects blend ratio to maintain product quality and also includes a correction for already blended product that may be out of specification.
Main controller features include 'blend enable input' operating as a failsafe dead-man's handle, PC-based configuration backup and 'restore', two-tier alarms or shutdown due to ratio deviation and integration into a user's DCS.
Compatible with ratio control, density trim and viscosity trim blender systems, and suitable for crude or bunker fuel oil, LNG/LPG and ethanol applications, plus chemical and liquid blending, the Inspec features access security and visual announcement of alarms with a hardware output.
