GE 760

6 - 4 750/760 FEEDER MANAGEMENT RELAY – COMMUNICATIONS GUIDE
BINARY / CONTROL RELAY OUTPUT CHAPTER 6: DNP POINT LISTS
1. The Count field is checked first. If it is zero, the command will be accepted but no
action will be taken. If this field is non-zero, the command will be executed exactly
once regardless of its value.
2. The Control Code field of object 12 is then inspected:
– The Queue, and Clear sub-fields are ignored.
– If the Code sub-field is NUL, then the command will be accepted without
any action being taken.
– A Code sub-field of “Pulse On” (1) is valid only for points 0 through 2. This
is used to activate the function (e.g., Reset) associated with the point.
– A Code sub-field of “Pulse On” (1) in combination with a value in the Trip/
Close sub-field form a “Trip” or “Close” value. A “Trip” value consists of a
“Pulse On” (1) in the Code sub-field and a 2 in the Trip/Close sub-field. This
results in a value of 81 (hex) in the Control Code field. A “Close” value con-
sists of a “Pulse On” (1) in the Code sub-field and a 1 in the Trip/Close sub-
field. This results in a value of 41 (hex) in the Control Code field.
– A Code sub-field of “Latch On” (3) or “Latch Off” (4) is valid for all virtual
input points (i.e., points 3 through 22). This is used to set the associated
Virtual Input on (“Latch On”) or off (“Latch Off”). As well, a “Close” value in
the Control Code field will cause the virtual input to be turned on while a
“Trip” value in this field will cause the virtual input to be turned off.
– The “Breaker Control” point (23) will only accept a “Trip” or “Close” value. A
value of “Trip” will activate the “Breaker Open” function. Similarly, a value
of “Close” will activate the “Breaker Close” function.
– All operations not defined above are invalid and will be rejected.
3. The On Time and Off Time fields are ignored. A “Pulse On” Code takes effect immedi-
ately when received, therefore timing is irrelevant.
4. The Status field in the response will reflect the success or failure of the control attempt
thus:
– A Status of “Request Accepted” (0) will be returned if the command was
accepted.
– A Status of “Request not Accepted due to Formatting Errors” (3) will be
returned if the Control Code field was incorrectly formatted or an invalid
Code was present in the command.
– A Status of “Control Operation not Supported for this Point” (4) will be
returned if an attempt was made to operate the “Open Breaker” (1), “Close
Breaker” (2) or “Breaker Control” (23) points and the relay is in local mode
(this status is indicated by Object 1, Point 14).
Setting or clearing a Virtual Input will always succeed, however an operate of the Reset,
Open Breaker, Close Breaker or Breaker Control points may fail (even if the command is
accepted) due to other inputs or conditions (e.g., blocks) existing at the time. To verify the
success or failure of an operate of these points it is necessary that the associated Binary
Input(s) be examined after the control attempt is performed.
When using object 10 to read the status of a Binary Output, a read of points 0 through 2
and 23 will always return zero. For other points, the current state of the corresponding
Virtual Input will be returned.