Endress+Hauser Tankvision Gauge Link NXA20, Руководство по эксплуатации

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Troubleshooting Tankvision Gauge Link
36 Hauser
If the Tankvision Gauge Link is being installed to replace an existing tank gauging host,
it may be possible to verify the prevailing field bus communications conditions before
attempting to install the Tankvision Gauge Link. This will assist in tracing subsequent
communications problems if they relate to incorrect configuration, or poor
communications/intermittent comms failures resulting from field conditions (bus
loading, noise/interference, etc.).
Host port RECEIVE ( ) LED
flickers but no activity on
TRANSMIT ( ) LED
Incorrect configuration:
• wrong communications
parameters (Baud rate, etc.)
• wrong protocol
• wrong Modbus slave address
Investigate and rectify.
Host and Tankvision Gauge Link
must be set to same comms
parameters.
Protocol is Modbus RTU.
Modbus requires 8 data bits for
RTU. Parity is usually “none” (not
needed for RTU)
Host port RECEIVE ( ) LED
flickers, intermittent or no
TRANSMIT (
) LED activity
Garbled communications:
• loose connection
• noise/interference
• Baud rate too high
Check wiring.
Check for sources of noise/
interference.
Try slower Baud rate.
Field port TRANSMIT ( ) LED
flickers but no activity on RECEIVE
(
) LED
Incorrect configuration:
• wrong field bus interface
• wrong communications
parameters (Baud rate, etc.)
• wrong protocol
• wrong gauge addresses
Investigate and rectify.
Tankvision Gauge Link must be set
to same comms parameters as
gauges.
Protocol must suit field bus
interface option.
Wiring fault between Tankvision
Gauge Link and gauges Investigate and rectify.
Check wiring.
Field port TRANSMIT ( ) LED
flickers, RECEIVE ( ) LED flickers
normally except periodic gaps in
activity at evenly spaced regular
intervals
Incorrect configuration:
• wrong data parameters
• requesting parameters that are
not supported by the gauge
• one or more wrong gauge
addresses
Investigate and rectify.
Tankvision Gauge Link must be set
to only request parameters that are
available from the gauges.
Check for incorrect or conflicting
gauge address.
Field port TRANSMIT ( ) LED
flickers, intermittent or no RECEIVE
(
) LED activity
Garbled communications:
• loose connection
• noise/interference
• Baud rate too high
• excessive bus loading
Check wiring.
Check for sources of noise/
interference.
Try slower Baud rate (subject to
protocol limitations).
Reduce number of gauges on field
bus. (see note)
Field port TRANSMIT ( ) and
RECEIVE ( ) LEDs flicker,
intermittent or no
COMMUNICATIONS (
) LED
activity
Symptom Possible cause Remedy