Section 7: Frequency converter control via RS-485 communication link
7.3. Handling communication errors
In case of transmission errors or sending a command with improper paramet-
ers, the system responds in the manner provided for by the MODBUS stand-
ard. Possible return error codes are:
Error №
Description
1
Unknown command—when a command other than 3 or 6
has been sent,
2
Wrong address—the register address is not supported by the
system (there is no such register),
3
Wrong value—an attempt was made to send a register value
outside the allowable range using the command 6.
In case of wrong transfer (e.g. CRC error) device does not send answers to
commands.
8. Failures and warnings
8.1. Messages on failures and warnings on the control panel
The luminescence of a red light-emitting diode LED (with a “FAULT” descrip-
tion) and the display of appropriate messages signal about failure state.
Thus, the frequency converter passes to STOP mode. To make the next
START, it is necessary to remove the cause and delete the fault report - see
section 6.2.
Warning state is signaled by the appropriate message on the display without
stopping the frequency converter. The removal of the warning notification is
done by removing its cause and pressing
.
Table 8.1. Failures and warnings codes
Code
Display view
Description
Possible cause
Counteraction
E. 1
Heat sink temperat-
ure higher than
80ºC.
Difficult airflow, sys-
tem overload, ambi-
ent temperature too
high.
Check ventilation ef-
ficiency (fan effi-
ciency and heat sink
contamination).
E. 3
High voltage in DC
circuit
Too high voltage in
the circuit, intensive
braking of the electric
motor.
Check mains supply.
Increase the braking
time (deceleration)
in par. 1.31.
TWERD Power Electronics
51
REF
Hz
rpm
RUN
REV
FAULT
REF
Hz
rpm
RUN
REV
FAULT