Communication Error Codes And Solutions; Troubleshooting - Mitsubishi Electric MDU-BN Instruction Manual

8.3 Communication error codes and solutions

(1) With CC-Link transmission option
Error code
Note: The numbers in parentheses are
in hexadecimal notation.
Digital command,
Standard command
analog command,
between devices
or pulse command
1 (01h)
16 (10h) 192 (C0h)
65 (41h) –
66 (42h) 193 (C1h)
81 (51h) 194 (C2h)
83 (53h) 209 (D1h)
Note: Errors other than those listed above are detected by the detector on the command transmission side. Refer to the Instruction Manual for that
device for details.
Note: If the error status flag (RX(n+1) A) is set once to " 1 " (ON), the error status flag will not be set to " 0 " (OFF) even if the CPU of PLC is reset.
To set the error status flag to " 0 " (OFF), set the error reset status flag (RY(n+1) A) to " 1 " (ON).
However, even if the error status is released when the error reset status flag is set to " 1 " (ON), if there is an error in the retransmitted data, the
error status flag will once again be set to " 1 " (ON). Therefore, refer to the error code and eliminate the cause of the error prior to retransmitting.
(2) With MODBUS transmission option
Error code Error details
01h Illegal function
02h Register address error
03h Data value error
04h Slave abnormality
06h Slave Busy
Note: Errors other than those listed above are detected by the detector on the command transmission side. Refer to the Instruction Manual for that
device for details.

8.4 Troubleshooting

Check the following if your device appears to be failing.
(1) Is the MDU applied control power?
(2) Nothing is displayed on the display.
Is the connection cable connector fully plugged in? Is it disconnected?
(3) The device is powered but the current is 0 A.
If the electric current measurement value is less than the measurement lower limit current (less than ± 1.0% of the measurement rated current),
it is cutoff so that the display value is 0 A.
(4) Unable to monitor when transmitting/communicating even though a value is displayed on the display.
[1] With CC-Link communication
• Confirm that there are no errors in the communication line connection, and that no wires are disconnected.
• Are there any stations with the same station number on the same transmission route? If there are, configure the correct station number and
then press the reset switch.
• Is the communication speed set to the same value as the master device? If it is different, configure the correct communication speed and then
press the reset switch.
[2] With MODBUS communication
• Confirm that there are no errors in the communication line connection, and that no wires are disconnected.
• Are there any stations with the same station number on the same transmission route? If there are, configure the correct address and then
press the reset switch.
• Is the communication speed set to the same value as the master device? If it is different, configure the correct communication speed and then
press the reset switch.
• Is the setting of the master unit and parity bit the same? If it is different, set the correct parity bit, then press the reset switch.
• Is the setting of the master unit and the stop bit the same? If it is different, set the correct stop bit, then press the reset switch.
(5) The electric current value measured by the device differs from other measurement values. (Permissible error value or greater.)
• Confirm that the measurement instrument used for comparison measures the effective value correctly. The device indicates the effective value.
• If the measurement instrument used for comparison measures the average value instead of the effective value, distortion in the current flowing
through the measurement circuit will create a significant difference.
Error details
Undefined command.
Hardware error.
Group number out of range.
Channel number out of range.
Setting value out of
configuration range.
Upper limit value and lower
limit value cross.
Solution
Please correct it to the correct function.
Please use the register described in MDU breaker programming manual MODBUS communication.
Please correct it to the correct data.
Please correct the setting value to the correct value.
Please review the timing of the query.
59
Solution
Set the correct command.
Turn the MDU control power supply OFF and then ON again,
or press the reset switch.
Set the group number to the correct value.
Set the channel number to the correct value.
Set the setting value to the correct value.
Set the upper limit value and lower limit value so that
they do not cross.