GE MiCOM P747 Agile, Technical Manual

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MCode MODBUS Description MiCOM Interpretation
02 Illegal Data Address
The start data address in the request is not an allowable value. If any of the addresses in
the range cannot be accessed due to password protection then all changes within the
request are discarded and this error response will be returned.
Note: If the start address is correct but the range includes non–implemented addresses this
response is not produced.
03 Illegal Value
A value referenced in the data field transmitted by the master is not within range. Other
values transmitted within the same packet will be executed if inside range.
06 Slave Device Busy
The write command cannot be implemented due to the database being locked by another
interface. This response is also produced if the software is busy executing a previous
request.
9.4 REGISTER MAPPING
The device supports the following memory page references:
● Memory Page: Interpretation
● 0xxxx: Read and write access of the output relays
● 1xxxx: Read only access of the opto inputs
● 3xxxx: Read only access of data
● 4xxxx: Read and write access of settings
where xxxx represents the addresses available in the page (0 to 9999).
A complete map of the MODBUS addresses supported by the device is contained in the relevant menu
database, which is available on request.
Note:
The "extended memory file" (6xxxx) is not supported.
Note:
MODBUS convention is to document register addresses as ordinal values whereas the actual protocol addresses are
literal values. The MiCOM relays begin their register addresses at zero. Therefore, the first register in a memory page
is register address zero. The second register is register address 1 and so on.
Note:
The page number notation is not part of the address.
9.5 EVENT EXTRACTION
The device supports two methods of event extraction providing either automatic or manual extraction of the
stored event, fault, and maintenance records.
9.5.1 AUTOMATIC EVENT RECORD EXTRACTION
The automatic extraction facilities allow all types of record to be extracted as they occur. Event records are
extracted in sequential order including any fault or maintenance data that may be associated with the event.
The MODBUS master can determine whether the device has any events stored that have not yet been
extracted. This is performed by reading the status register 30001 (G26 data type). If the event bit of this
register is set then the device has non-extracted events available. To select the next event for sequential
extraction, the master station writes a value of 1 to the record selection register 40400 (G18 data type). The
event data together with any fault/maintenance data can be read from the registers specified below. Once
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