Error diagnosis and remedies
26
Trebing & Himstedt | SPI 3 | MODBUS RTU
Note!
If errors occur during communication, the DP master runs a PROFIBUS
diagnosis. Evaluation of this diagnosis depends on the used DP master.
When using a bus monitor (e.g. the PROFIBUS Scope), you can additionally
evaluate diagnosis telegrams. For data of this device-related diagnosis, see
»Evaluating PROFIBUS diagnosis telegrams« on page 19.
RUN LED code Status
Significance
Remedy
RUN LED off
SPI 3 not ready
– 24 V supply not present
– Check external power
supply
– Check the wiring
RUN LED
medium
Receive error
No response from
slave
– Error when receiving
– MODBUS slave did not
respond after max. number
of repeats
– Check parameters of all
modules (the SPI 3 is
MODBUS master)
– Check the address of the
MODBUS slave
– Check the wiring
RUN LED on
Communication OK
– MODBUS slave communi-
cating correctly with the
SPI 3
– SPI 3 working correctly
