Michell Instruments QMA401, Руководство пользователя

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QMA401 User’s Manual
Michell Instruments 1
INTRODUCTION
1 INTRODUCTION
1.1 General
The QMA401 Moisture Analyzer is designed to provide reliable, fast and accurate
measurement of trace moisture content in a wide variety of applications where keeping
moisture levels as low as possible is of critical importance.
The high-contrast LCD touchscreen display presents all measured data to the user in a
clear and understandable format. The main display incorporates a real-time trend graph
and alarm indicators based on the NAMUR 102 standard. A powerful and intuitive HMI
makes control, logging and configuration of analyzer parameters straightforward.
The instrument provides two user-configurable analog outputs, and ModBus RTU/TCP
communications, allowing it to interface with a SCADA DCS, or by a computer using the
dedicated application software. A pair of adjustable isolated alarm contacts allow the
QMA401 to be used for direct process control.
T he QMA401 offers:
• ModBus RTU/TCP
• Datalogging to SD Card
• 2 user-configurable analog outputs
• Status and Process Alarms
Minimal & Straightforward Maintenance
Sophisticated instruments are often complicated and require experience and special care
in use, increasing cost of ownership. The QMA401 differs through its very uncomplicated
approach to field service; the desiccant column is easy to replace via the dryer service
panel on the rear of the instrument. The moisture generator has an average life span of
3 years before maintenance is required.
Automated Calibration for Continued Reliability
The QMA401 incorporates an integrated automatic calibration system for complete
user confidence. Periodic calibration checks of sensor performance can be initiated
on demand, or automatically (at user defined intervals and time of day), providing a
verification against the calibrated moisture generator or an external reference. The
moisture generator at the core of this system is supplied with a calibration traceable to
NPL and NIST.
During an internal calibration cycle, the Data Hold function will prevent any interruption
of dependant processes by holding the analog outputs at the same level for the duration
of the calibration.
Integrated Sample Handling Components
The QMA401 features an optional bypass arrangement to increase transport speed of
the sample.
A pressure regulator can also be specified to increase the range of acceptable input
pressure (rated to 300barg input pressure), and to protect the instrument against
pressure shocks.