GE P24DM, Technical Manual

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MODBUS Register Name Description
4x00250
Manual disturbance record
selection register
This register is used to manually select disturbance records. The values
written to this cell are an offset of the unique identifier value for the
oldest record. The offset value, which ranges from 0 to the Number of
stored disturbances - 1, is added to the identifier of the oldest record to
generate the identifier of the required record.
4x00400
Record selection command
register
This register is used during the extraction process and has a number of
commands. These are:
b0: Select next event
b1: Accept event
b2: Select next disturbance record
b3: Accept disturbance record
b4: Select next page of disturbance data
b5: Select data file
3x00930 - 3x00933 Record time stamp These registers return the timestamp of the disturbance record.
3x00802 No of registers in data page
This register informs the master station of the number of registers in the
data page that are populated.
3x00803 - 3x00929 Data page registers
These 127 registers are used to transfer data from the relay to the master
station. They are 16-bit unsigned integers.
3x00934
Disturbance record status
register
The disturbance record status register is used during the extraction
process to indicate to the master station when data is ready for
extraction. See next table.
4x00251 Data file format selection
This is used to select the required data file format. This is reserved for
future use.
Note:
Register addresses are provided in reference code + address format. E.g. 4x00001 is reference code 4x, address 1 (which is
specified as function code 03, address 0x0000 in the MODBUS specification).
The disturbance record status register will report one of the following values:
Disturbance record states
State Description
Idle
This will be the state reported when no record is selected; such as after power on or after a record has been
marked as extracted.
Busy The relay is currently processing data.
Page ready The data page has been populated and the master station can now safely read the data.
Configuration complete All of the configuration data has been read without error.
Record complete All of the disturbance data has been extracted.
Disturbance overwritten
An error occurred during the extraction process where the disturbance being extracted was overwritten by a
new record.
No non-extracted disturbances
An attempt was made by the master station to automatically select the next oldest non-extracted
disturbance when all records have been extracted.
Not a valid disturbance An attempt was made by the master station to manually select a record that did not exist in the relay.
Command out of sequence The master station issued a command to the relay that was not expected during the extraction process.
6.4.6.1 MANUAL EXTRACTION PROCEDURE
The procedure used to extract a disturbance manually is shown below. The manual method of extraction does not
allow for the acceptance of disturbance records.
P24xM Chapter 16 - Communications
P24xM-TM-EN-2.1 341