7.2 Troubleshooting the transmitter
Device not visible on the network
If a device cannot be seen on the fieldbus network, the device may not be powered up or possibly
the supervisory or control program is not able to find (or polling) the node address of that device.
See the following table for possible causes and recommended actions.
Possible cause
No power to the
device.
Insufficient current to
the device.
More than two or less
than two terminators
are wired to fieldbus
link.
Insufficient signal to
the device.
Names of parameters
are not visible.
Rev.5
Symptoms
Device not visible on the network
Things to check
Measure the DC voltage at the
device's SIGNAL terminals.
Voltage must be within the limits.
Measure the DC current / voltage
ranges to the device. The DC
current / voltage ranges must be
within the limits.
Check to see that only two
terminators are present on a link.
Measure the peak-to-peak signal
amplitude. The output must be
0.75 to 1.0Vp-p.
Measure the signal on the + and -
SIGNAL terminals and at a
frequency of 31.25k Hz.
Missing or incorrect version of
Device Description file on host
computer.
FOUNDATION Fieldbus Option User's Manual
Recommended action
If no voltage or voltage is out
of operating limits, determine
the cause and correct it.
If the current / voltage is
insufficient, determine the
cause and correct it.
Correct, if necessary.
If the signal amplitude is
insufficient, determine the
cause and correct it.
Check the loaded Device
Description.
Load correct version of DD.
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