GE Hydran 201i, Инструкция по эксплуатации

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Chapter 11 • Operating the Hydran 201
i
System
11-4 Rev. 6, March 2011 Part 17997
11.1.3.2 Conclusion
Because of the above limitations and because it is not possible to change the
Hydran 201
i System’s parameters from the control room, we can conclude that the analog
output monitoring method (gas level monitoring via the analog output) still requires that a
host computer be connected to the Hydran 201C i Controller to retrieve the Hydran 201T i ’s
historic data and modify parameters.
11.1.4 Combined Alarm and Analog Output Monitoring
As the name implies, this method combines the two previous monitoring methods. The
major advantage of this method is its familiarity. Its limits become apparent when one reads
the text on the two previous methods:
• Although the gas level, the gas alarms (gas level, hourly trend and daily trend) and fail
alarm are now available at the same time, important information is still confined to the
Hydran 201T
i .
• Accessing the H201T i is still required to modify operation parameters.
• The amount of cabling becomes an important issue. For each H201T i , a minimum of four
pairs of wires is required to connect the analog output, the two gas alarms and the fail
alarm. To
receive this information, three digital inputs and one analog input must be
available in the SCADA system.
11.1.5 Local Monitoring With Host Computer
The local monitoring with host computer method consists of connecting a host computer
running the Hydran Host software to a Hydran 201 i System or a network using an RS-232
serial communication link.
Note: An RS-232 or USB communication port is available on each Hydran 201Ci
Controller.
The Hydran Host software allows numerous tasks, among which:
• Data reading (gas level, hourly and daily trends, etc.)
• Immediate detection of all alarms and their acknowledgment by the user
• Modification of alarm settings and other parameters
• Historic data upload from one or several Hydran 201T
i ’s