User Manual

4 - 5
IPN 074-289L
Composer Operating Manual
4.3 How To Use The Instrument
The following sections explain how to start, stop, and shut down the instrument.
A description and purpose of the operating modes, displays, and system I/O
connectors is also provided.
4.3.1 How To Start The Instrument
Operating the instrument requires a 24 V power connection and the POWER
switch in the on position (POWER LED illuminated).
NOTE: The proper operation of all LED displays may be visually verified when
the POWER switch is cycled on. All LEDs are illuminated for
approximately two seconds after the power switch is activated.
4.3.1.1 Concentration Control Configuration
This Instrument System will attempt to measure concentration whenever power
is applied and the green POWER indicator is illuminated on the Controller. It will
give correct answers when the pressure is within the specified range and
correct values for the gasses Molecular Weights and Specific Heat Ratios have
been entered (refer to Table 3-1 on page 3-3) and the factory set Reference
Zero is used. In addition, if a new Reference Zero is set, the proper procedure
for the establishment of the Reference Zero with the correct pure calibration
gas must be followed or incorrect concentration values will be output (refer to
section 4.2.3, How to Calibrate, on page 4-3). Control of precursor
concentration requires that the control loop parameter value be set as
described in section 3.2.1, Control Loop Fundamentals — Concentration
Control, on page 3-21 and in section 3.2.1.5, Computing the System’s Time
Constant, on page 3-25.
4.3.1.2 Bulk Flow Control Configuration
All instrument function is controlled externally through Input #4 of the system
I/O connector. Refer to section 3.1.13 on page 3-11.
4.3.2 How To Stop The Instrument
4.3.2.1 Concentration Control Configuration
The Instrument will stop controlling concentration by pressing the STOP key on
the optional LCD display, applying a closure to pin #20 (STOP) on the SYSTEM
I/O connector, or pressing the STOP function in the optional Monitor software.
The control function may be restored by applying a closure to pin #21 (START)
or pressing the START function key in the Composer Monitor Software.
NOTE: HOLD, STOP, BYPASS, and START are mutually exclusive functions
and the function will be dictated by the last command executed.