AMI 210BR, Руководство пользователя

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AMI Analyzer Manual Analyzer Description
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sensor to come back down to a low reading on the sample. Then perform a span gas calibration only don’t
adjust the span factor, and see what the analyzer says the gas contains. If the gas value isn’t what you think
it should be, it is the gas that is wrong, not the analyzer, because that air calibration is in fact very valid. You
will have to trouble shoot whatever has happened with your gas.
Using the analyzer
Output Range
The analyzer displays the oxygen level in appropriate units on the LCD, automatically adjusting its sensitivity
as required. Meanwhile the analog output and the alarms (as well as the data log) are set on a single (user
selectable) “Output” range.
For example, you can set the analog output to correspond to 0-10%, and the alarms to be 4.0% and 5.0%
(i.e. 40% and 50% of range), activating above set point. If the oxygen level actually is 2.5%, the display will
show 2.50%, and the output signal will be at 25% of full scale. If the oxygen level becomes 20.0%, the
display will show 20.0%, but the 4-20mA output will be saturated, and the alarms will both be activated.
If you now manually change the output range to 0-25%, the reading will stay at 20.0%, the 4-20mA output
will go to 80% of scale, and the alarms will de-activate, since they now correspond to 10.0% and 12.5%, i.e.
still 40% and 50% of range. However if the alarms were set to latch, you would have to acknowledge them
by pressing the ALARM BYPASS button before they would de-activate.
Output ranges 0-1%, 0-5%, 0-10%, 0-25%.
Security:
Through the user interface, three levels of security can be set. These are: No security (all front panel
controls are active), Span (only the span control and the ALARM BYPASS button are allowed to operate), and
Full security (only the ALARM BYPASS button performs a function; other buttons will show settings but
won’t allow them to be changed). If the front panel controls don’t seem to work, use the AMI User Interface
to change the security settings.
Communications
The 210BR supports both a USB link to a local PC, and RS485 over a network. Only one of these can be
active at a time, and the unit automatically turns off the RS485 if it detects a computer plugged into the USB
connection. Therefore the PC connection over the USB has priority.
The USB connection supports the proprietary AMI protocol, and AMI provides a program on a CD that
interfaces with the analyzer. Alternatively it is possible for someone familiar with communications on a PC
to directly use the protocol. See the AMI communications manual for details.
The RS485 port supports ModBus RTU at 9600 baud.
These are described in the various communications manuals available on the web site.