
15
INM F809F-2C rev 2 15
c) In normal operation, with greater than 100,000 Pass Tokens monitored, the F809F displays a moving average
retransmission rate that avoids nuisance alarms from typical events whilst providing good response to changes in fieldbus
communications performance.
Note 2. The hour means a 60 minute period starting at "the top of the hour" e.g. 0900 to 1000 or 5pm to 6pm.
Note 3. The device signal level high limits and peak noise high alarm limits with fieldbus software version 1.10 or earlier are:
Device Signal Level Limits - High 1000mV
Peak Low Frequency Noise 300mV
Peak In-band Frequency Noise 150mV
Peak High Frequency Noise 300mV
4.2.5.1 SEGMENT_ALARMS - Descriptions and Corrective Actions
Dec. value Hex Value Name and Description Help Text
2147483648 0x80000000 Segment Voltage High-High Alarm Check fieldbus power supply operation
1073741824 0x40000000 Segment Voltage High Alarm
536970912 0x20000000 Segment Voltage Low Alarm Check fieldbus power supply operation
268435456 0x10000000 Segment Voltage Low-Low Alarm
134217728 0x08000000 Average Low Frequency Noise
High-High Alarm
Check: fieldbus screening is correctly cut back and taped at each
end of the fieldbus device; fieldbus screen connections are cor-
rectly made in Fieldbus Barrier Junction Box, intermediate junction
boxes, in marshalling cabinet, FP32 surge protector and connect-
ed to F618D and grounding connection of F618D; AC cabling
close to fieldbus cabling; wire terminations are properly secured.
67108864 0x04000000 Average Low Frequency Noise
High Alarm
33554432 0x02000000 Average In Band Frequency Noise
High-High Alarm
Check: fieldbus screening is correctly cut back and taped at each
end of the fieldbus device; fieldbus screen connections are correctly
made in Fieldbus Barrier Junction Box, intermediate junction boxes,
in marshalling cabinet, FP32 surge protector and connected to
F618D and grounding connection of F618D; AC cabling close to
fieldbus cabling; wire terminations are properly secured. Check for
welding on plant or poor grounding of frequency controlled drives.
16777216 0x01000000 Average In Band Frequency Noise
High Alarm
8388608 0x00800000 Average High Frequency Noise
High-High Alarm Check: for sources of high frequency noise such as welding on
plant, poor grounding of frequency controlled drives.
4194304 0x00400000 Average High Frequency Noise
High Alarm
2097152 0x00200000 Peak Low Frequency Noise
High-High Alarm
If frequent alarms, check: fieldbus screening is correctly cut back
and taped at each end of the fieldbus device; fieldbus screen
connections are correctly made in Fieldbus Barrier Junction Box,
intermediate junction boxes, in marshalling cabinet, FP32 surge
protector and connected to F618D and grounding connection of
F618D; AC cabling close to fieldbus cabling; wire terminations
are properly secured.
1048576 0x00100000 Peak Low Frequency Noise
High Alarm
524288 0x00080000 Peak In Band Frequency Noise
High-High Alarm
If frequent alarms, check: for operation of radios with Effective
Radiated Power (ERP) of up to 5W being used within 1.5m of field-
bus devices, junction box or cabling; fieldbus screening is correctly
cut back and taped at each end of the fieldbus device; fieldbus
screen connections are correctly made in Fieldbus Barrier Junction
Box, intermediate junction boxes, in marshalling cabinet, FP32
surge protector and connected to F618D and grounding connec-
tion of F618D; AC cabling close to fieldbus cabling; wire termi-
nations are properly secured. Check for welding on plant or poor
grounding of frequency controlled drives.
262144 0x00040000 Peak In Band Frequency Noise
High Alarm
131072 0x00020000 Peak High Frequency Noise
High-High Alarm
If frequent alarms, check: for operation of radios with Effective
Radiated Power (ERP) of up to 5W being used within 1.5m of field-
bus devices, junction box or cabling; for welding on plant or poor
grounding of frequency controlled drives.
65536 0x00010000 Peak High Frequency Noise
High Alarm
32768 0x00008000 Live Device Count High Alarm
Check if additional device has been added to segment, if new
device is approved and segment documentation has been updat-
ed, reset live device count limits;