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Technical Specifications and Operational Parameters
12.15
Limit Alarms
Limit alarms may currently be defined and set through PSCSV software and include alarming to
the display, memory and through any of the communication channels.
Functions
Upper or lower limits may be set on most measured
functions. Limits may also be set on maximum imbalance
(ratio of Zero and Negative Sequence Components to
Positive Sequence).
Output
Via system interface and display or contact closure
Interface
Configure and read with PSCSV (see “Configuring Mul-
timode Relays” in Section 7.10).
12.16
System Control and Monitoring
Combining DSP and GNSS technology, the 1133A can measure time-dependent electrical system
quantities and display them on the front panel or record them for future use. To record System
Time, Phase and Frequency data, see Chapter 7 on using PSCSV software.
12.16.1
System Time, Phase and Frequency
“System” refers to the electrical system under measurement. By comparing the generated system
time and frequency to the GNSS signal as a reference, the 1133A can measure and record the
(integrated) difference in time and frequency, as well as other time-related system facts.
System Time
Unlimited accumulation with
±
1-
µ
s resolution
Frequency
7 digits, xx.xxxxx Hz
System Phase
0
−
360 degrees with 0.01 degree resolution
Effect of DC
None; Rejected by narrow band digital filtering
12.16.2
Phasors
Standard
Per IEEE Synchrophasor Standard C37.118
Rate
Depends on nominal frequency; 1
−
50 measurements per
second for 50 Hz, 1
−
60 measurements per second for 60
Hz
Interface
User configured through PSCSV (see Configure Ports –
C37.118 Synchrophasor Protocol). Uses SERIAL 1 and
SERIAL 2 (RS-232, RS-485 or Modem) and the Ethernet
port, and UDP Broadcast mode uses the Ethernet port.