Reference Manual
00809-0100-4697, Rev EA
October 2011
Rosemount 848T
4-4
TROUBLESHOOTING
FOUNDATION fieldbus
Resource Block
Transducer Block Troubleshooting
Symptom Possible Cause Corrective Action
Device does not show
up in the live list
Network configuration parameters
are incorrect
Set the network parameters of the LAS (host system) according to the FF
Communications Profile
ST: 8
MRD: 4
DLPDU PhLO: 4
MID: 7
TSC: 4 (1 ms)
T1: 96000 (3 seconds)
T2: 9600000 (300 seconds)
T3: 480000 (15 seconds)
Network address is not in polled
range
Set first Unpolled Node and Number of UnPolled Nodes so that the device
address is within range
Power to the device is below the
9 VDC minimum
Increase the power to at least 9V
Noise on the power /
communication is too high
Verify terminators and power conditioners are within specification
Verify that the shield is properly terminated and not grounded at both ends. It is
best to ground the shield at the power conditioner
Device that is acting as
a LAS does not send
out CD
LAS Scheduler was not
downloaded to the Backup LAS
device
Ensure that all of the devices that are intended to be a Backup LAS are
marked to receive the LAS schedule
All devices go off live
list and then return
Live list must be reconstructed by
Backup LAS device
Current link setting and configured links settings are different. Set the current
link setting equal to the configured settings.
Symptom Possible Causes Corrective Action
Mode will not leave
OOS
Target mode not set Set target mode to something other than OOS.
Memory Failure BLOCK_ERR will show the lost NV Data or Lost Static Data bit set. Restart the
device by setting RESTART to Processor. If the block error does not clear, call
the factory.
Block Alarms Will not
work
Features FEATURES_SEL does not have Alerts enabled. Enable the report bit.
Notification LIM_NOTIFY is not high enough. Set equal to MAX_NOTIFY.
Symptom Possible Causes Corrective Action
Mode will not leave
OOS
Target mode not set Set target mode to something other than OOS.
A/D board check sum error The A/D board has a checksum error.
Resource block The actual mode of the Resource block is in OOS. See Resource Block
Diagnostics for corrective action.
Transducer Block The actual mode of the Transducer Block is OOS.
The primary value is
BAD
Measurement Look at the SENSOR_STATUS parameter (See Table 3-16 on page 3-21)