Phasor Measurement Unit One-Shot - GE N60 Instruction Manual

CHAPTER 7: COMMANDS AND TARGETS
Various self-checking diagnostics are performed in the background while the N60 is running, and diagnostic information is
stored on the non-volatile memory from time to time based on the self-checking result. Although the diagnostic
information is cleared before the N60 is shipped from the factory, the user can want to clear the diagnostic information for
themselves under certain circumstances. For example, you clear diagnostic information after replacement of hardware.
Once the diagnostic information is cleared, all self-checking variables are reset to their initial state and diagnostics restart
from scratch.
— Saves this data to compact flash memory prior to shutdown. This allows the saved data to be as
SAVE VOLATILE DATA
recent as possible instead of relying on the periodic timer to save the data.

7.1.5 Phasor Measurement Unit one-shot

COMMANDS  PMU ONE-SHOT
 COMMANDS
 PMU ONE-SHOT
This feature allows pre-scheduling of a PMU measurement at a specific point in time. It can be used to test for accuracy of
the PMU and for manual collection of synchronized measurements through the system, as explained here.
When enabled, the function continuously compares the present time with the pre-set
times match, the function compares the present sequence number of the measured synchrophasors with the pre-set
. When the two numbers match, the function freezes the synchrophasor actual values and the
ONE-SHOT FRACTIONAL SEC
corresponding protocol data items for 30 seconds. This allows manual read-out of the synchrophasor values for the pre-
set time and pre-set sequence number (via the faceplate display, supported communication protocols such as Modbus or
DNP, and the EnerVista UR Setup software).
When freezing the actual values, the function also asserts a
configured to drive an output contact and trigger an external measuring device such as a digital scope with the intent to
verify the accuracy of the PMU under test.
With reference to the following figure, the PMU one-shot function (when enabled) controls three FlexLogic operands:
• The
PMU ONE-SHOT EXPIRED
at least 30 seconds past the scheduled one-shot time
• The
PMU ONE-SHOT PENDING
before the scheduled one-shot time
• The operand indicates the one-shot operation and remains asserted for 30 seconds afterwards
PMU ONE-SHOT OP
When the function is disabled, all three operands are de-asserted.
The one-shot function applies to all logical PMUs of a given N60 relay.
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
PMU ONE-SHOT

FUNCTION: Disabled
PMU ONE-SHOT

FRACTIONAL SEC: 0
PMU ONE-SHOT TIME:

2013/06/14 7:58:35
PMU ONE-SHOT OP
operand indicates that the one-shot operation has been executed, and the present time is
operand indicates that the one-shot operation is pending; that is, the present time is
Range: Enabled, Disabled
Range: 0 to 99 in steps of 1
Range: YYYY/MM/DD HH:MM:SS
PMU ONE-SHOT TIME
FlexLogic operand. This operand can be
COMMANDS MENU
. When the two
PMU
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