GE Power Quality Meter Series Instruction Manual page 253

APPENDIX A
a) ACCESS TO EVENT RECORDER INFORMATION:
There are two ways to access Event Recorder Information:
• Access only the Records and data you wish to view
• Access the entire Event Record.
The Event Recorder is indexed by Event Number (1 to 40). To access a specific Event, the Event Number must
be written to the PQM memory map location 12C0h. The data specific to that Event can be read starting at
memory map location 0AE0h. The specific Event Number must be known to read the Event Recorder in this
fashion. However, this Event Number is usually not known and the entire Event Record must be read. The eas-
iest way to do this is to read the PQM Memory Map location 0AD0h (Total Number of Events Since Last Clear)
and loop through each Event Number indicated by the value from 0AD0h, reading the associated data pertain-
ing to each Event. This require from 1 to 40 serial reads of 170 bytes each. Once this data is obtained, it can be
interpreted based upon the format of each value as described in Section 7.3: MODBUS MEMORY MAP. It is
important to note that some memory map parameters are 32 bits (4 bytes) long and require 2 registers to con-
tain their value, one for the two high bytes and one for the two low bytes.
GE Power Management PQM Power Quality Meter
A.1 PQM APPLICATION NOTES
A
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