Mitsubishi Electric FR-F820-00046 Instruction Manual page 482

• The following charts show operations when a communication option fault occurs.
Pr.502 = "0 (initial value) or 3"
Fault occurrence
OFF
Fault
Fault display
(E.1)
Fault output
OFF
(ALM)
Alarm output
OFF
(LF)
Pr.502 = "4"
Fault occurrence
OFF
Fault
Warning display
(CF)
Fault output
OFF
(ALM)
Alarm output
OFF
(LF)
NOTE
• Fault output indicates the Fault (ALM) signal and an alarm bit output.
• When the fault output is set enabled, fault records are stored in the fault history. (A fault record is written to the fault history at
a fault output.)
• When the fault output is not enabled, fault record is overwritten to the fault history temporarily but not stored.
• After the fault is removed, the fault indication goes back to normal indication on the monitor, and the fault history goes back to
the previous status.
• When Pr.502 ≠ "0", the normal deceleration time setting (settings like Pr.8, Pr.44, and Pr.45) is applied as the deceleration
time. Normal acceleration time setting (settings like Pr.7 and Pr.44) is applied as the acceleration time for restart.
• When Pr.502 = "2, 3, or 4", the inverter operates with the start command and the speed command, which were used before
the fault.
• If a communication line error occurs, then the error is removed during deceleration while Pr.502 = "2", the motor re-accelerates
from that point.
• The Pr.502 and Pr.779 settings are valid when communication is performed via the RS-485 terminals or a communication
option.
• These parameters are valid under the Network operation mode. When performing communication through RS-485 terminals,
set Pr.551 PU mode operation command source selection ≠ "1".
• Pr.502 is valid for the device that has the command source under the Network operation mode. If a communication option is
installed while Pr.550 = "9999 (initial setting)", a communication error in RS-485 terminals occurs and Pr.502 becomes invalid.
• If the communication error setting is disabled with Pr.335 = "9999" or Pr.539 = "9999" while Pr.502 = "3 or 4", the inverter does
not operate with the frequency set in Pr.779 when a communication error occurs.
• If a communication error occurs while continuous operation at Pr.779 is selected with Pr.502 = "3 or 4", the inverter operates
at the frequency set in Pr.779 even though the speed command source is at the external terminals.
Example) If a communication error occurs while Pr.339 = "2" and the RL signal is input through an external terminal, the
operation is continued at the frequency set in Pr.779.
Fault removal
ON OFF
Motor coasting
Time
Display
ON
Fault removal
ON OFF
Pr.779 = "9999" Pr.779 = "9999" Pr.779 = "9999"
Pr.779
Pr.779 ≠"9999"
(Runs at the frequency setting of Pr.779)
Time
Display
ON
Pr.502 = "1 or 2"
Fault occurrence
OFF
Fault
Fault display
(E.1)
Fault output
OFF
(ALM)
Alarm output
OFF
(LF)
5.12 (N) Communication operation parameters
Fault removal
ON OFF
Decelerates to stop
Time
Display
ON
5. PARAMETERS
1
2
3
4
5
6
7
8
9
10
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