8-26
Limit Data Pointers (45077-45204): These Registers indicate which values are being monitored
by Limits. Each Data Pointer has the following 8-byte structure:
ALine Number is an index into the Communication Table. Example: Line Number 11 is for the
12th Line in the Communication Table, 0.1 Second Phase-to-Neutral Voltages. Data Pointers with
Line Numbers greater than the number of lines in the table are ignored.
APoint Number is an index into a Line in the Communication Table. Example: Point Number 1 is
for the second entry in a Line. Line Number 11, Point Number 1 is the 2nd in the 12th line, 0.1
Second VBN. Data Pointers with Point Numbers greater than the number of points for the line are
ignored.
Latched Exception Flag (41105): This Register tells you how many Limit Triggers have occurred
since the last time the Registers were checked. This Register is Read Only.
Example: Two Limit Exceptions occurred. Read the Register from Port 1; you will notice 2 Limit
Exceptions returned. Later, two more Limit Exceptions occurred. Read the Register again. From
Port 1, you will notice 2 Limit Exceptions returned. From Port 2, you will notice 4 Limit
Exceptions returned. Limit Exceptions are incremented so that you have a history of Limit
Exceptions in the Ports.
Byte Format Range Description
0 Binary 0-99 Century
1 Binary 0-99 Year
2 Binary 1-12 Month
3 Binary 1-31 Day
4 Binary 0-23 Hour
5 Binary 0-59 Minute
6 Binary 0-59 Second
7 Binary 0-99+MSB Centisecond
Size Format Description
2-byte Unsigned Integer Line Number
1-byte Unsigned Char Point Number
1-byte Unsigned Char Limit Mode
2-byte Unsigned Integer Comparison 1 Value
2-byte Unsigned Integer Comparison 2 Value