MKS MKSINST IE1000A, Инструкция по эксплуатации

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Chapter One: General Information Introduction
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Chapter One: General Information
Introduction
MKS Instruments IE500A / IE1000A High Flow Rate Mass Flow Controller provides state-of-the-art
technology to meet the stringent requirements of advanced industrial manufacturing processes. The MFC
integrates thermal sensor technology together with MKS model based, adaptive, real-time feedback control to
provide typical flow control response times of approximately 2 seconds to changes in setpoint.
The product is available with full scale flow ranges of 250 – 500 slm (IE500A) and 501 - 1000 slm (IE1000A)
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equivalent in multiple process fitting connections and control interfaces. Both analog I/O and 4-20 mA I/O
interfaces are available as product options. The IE500A / IE1000A Mass Flow Controller includes an
embedded, web-based user interface.
The IE500A / IE1000A High Flow Rate Mass Flow Controller provides IP66 compliance against water and
dust ingress for critical industrial processes.
Performance Advantages
Increases Process Throughput and Stability

Provides accurate flow control for both the calibration and the user selected process gases.

Enables better process performance through increased MFC accuracy, reproducibility, and
repeatability.

Reduces MFC inventory through multi-gas, multi-range availability.
Reduces Overall Costs

Minimizes overall footprint of gas delivery module.

Includes embedded diagnostics interface that allows users to check MFC functionality without
removing the MFC.

Increases uptime through reduction of “No Problem Found” MFC replacements.

Reconfigures quickly through auxiliary digital interface for enhanced operation flexibility
How the MFC Works
The MFC compares the actual flow reading from an advanced 2-element thermal flow sensor to the desired
setpoint flow rate, and positions the low power, solenoid operated, pilot proportional control valve to
maintain, or achieve, the desired setpoint flow rate.
Upon entering the MFC, the process gas stream passes first through the metering section of the instrument
which consists of a small bore sensor tube operating in parallel with a precision formed bypass. The geometry
of the sensor tube ensures fully developed laminar flow in the sensing region. The bypass elements are
specifically matched to the characteristics of the sensor tube to achieve optimum performance throughout
each flow range.
The optimized sensor/bypass arrangement minimizes the flow splitting error for gases with different
properties, which dramatically improves measurement accuracy when gases other than the calibration gas are
used.
The flow measurement is based on differential heat transfer between temperature sensing heater elements
which are attached to the exterior of the sensor tube. The bridge circuitry senses the thermal mass movement
which is converted to mass flow via the specific heat, Cp, of the gas. Specialized circuitry and algorithms are
used to compensate for ambient temperature changes and minor attitude (product mounting orientation)
effects.