GE 489 - Manual (Page 207)

GE Multilin 489 Generator Management Relay 6-45
6 COMMUNICATIONS 6.5 DNP POINT LISTS
6
6.5.2 BINARY / CONTROL RELAY OUTPUT BLOCK (OBJECTS 10/12)
The following restrictions should be noted when using object 12 to control the points listed in the above table.
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 Control Code field is zero (i.e., NUL operation) the command is accepted but no action is taken.
• For all points, the only valid control is “Close - Pulse On” (41 hex). This is used to initiate the function (e.g., Reset)
associated with the point.
• Any value in the Control Code field not specified above is invalid and will be rejected.
3. The On Time and Off Time fields are ignored. A ”Pulse On” control takes effect immediately when received. Thus, the
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 incor-
rectly 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
point and the relay, owing to its configuration, does not allow the point to perform its function.
An operate of the Reset point 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 this point 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 any Binary Output, a value of zero will always be returned. This is due to the fact
that all points are “Pulse On” and are deemed to be normally off.
Table 6–6: BINARY OUTPUT POINT LIST
INDEX DESCRIPTION
0 Reset
1 Generator Start
2 Generator Stop
3 Clear Trip Counters
4 Clear Last Trip Data
5 Clear MWh and Mvarh
6 Clear Peak Demand Data
7 Clear Generator Information
8 Clear Breaker Information