Oil Heater Average Value Control

Overview

Oil heaters are used in the petrochemical and pharmaceutical industries to control the temperature of crude and reagent inside storage tanks and keep it within a certain range. Since the temperature of each point in the tank varies, you can avoid having to control the temperature of individual points by taking the average temperature and using the result as a control input value. With conventional controllers it was necessary to install several external computing units, but with the SMARTDAC+ measuring and control station the averaging is performed with an internal computing function, and the result can be input for controlling temperature.

Process outline

• Input from multiple temperature sensors installed inside of the tank
• Calculate averaged temperature value from six varying points
• Carries out temperature control by using the average as a control input value

Oil Heater Average Value Control Process

Customer Needs

• Local controller that provides reliable, 24-hour, 365-day continuous operation
• Calculate the average temperature from six varying points
• Control temperature by using the results of averaging as control input values
• Less programming solution
• Record steam pressure, flow, and other phenomena for total system monitoring

Yokogawa's Solution

GX20, GX90UT

• Take multiple temperature data from the oil heater with GX20 and GX90XA
• Calculate average value from input values with MATH option (/MT)
• Realize ideal temperature control of oil heater using average value as EXPV
• Measurement, display and recording of multiple points of analogue  input are available with a single GX20 unit
• Ethernet communication is available as  standard function.  It enables facilitates remote monitoring from control room

Customer Benefits

• Simple user interface and less programming solution with mathematical option
• High reliable recording and control unit including disconnected sensor detection
• Integrate average calculation, control and recording function into one device
• Saving space and cost for installing instruments

SMARTDAC+ Paperless Recorder / Data Logger

A broad range of data collection and control with excellent reliability and user-friendliness

Touch Screen GX10/GX20, GP10/GP20

• Vertical panel mount
• 12.1" TFT color LCD
• Up to 100 channels (built-in), 450 channels (with expansion unit)
• Maximum 1.2 GB internal memory
• Up to 32 GB SD/SDHC card
• Ethernet (built-in)

PID Control Module GX90UT

• 2 loops per module
• 2 analog inputs: universal input
• 2 control outputs: current, voltage pulse
• 8 Digital inputs, 8 Digital outputs (Open corrector)
• Control interval: 100ms, 200ms
• 4 alarm per loop