5-290
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
CONTROL ELEMENTS
CHAPTER 5: SETTINGS
5
Typical applications of the
8BIT COMP 1 BLOCK
setting include conditions when the input signals are not reliable. For
example, remote power can be digitized using the digitizer feature and sent via remote inputs/outputs to be used locally
by the eight-bit comparator. The VT fuse fail at the remote location, or the
REMOTE DEVICE OFFLINE
indication can be used to
block this element.
Figure 5-159: Eight-bit comparator logic
Application example
A three-phase active power measured via SRC 1 on the UR-1 IED is to be sent to a remote location UR-2 via the direct
inputs/outputs feature. Upon reception the remote power is to be added to a three phase active power measured locally
by the UR-2 IED via SRC 4. The application needs to be accurate under an overload of 25% and a power factor of 1.0 at
either location. An alarm is to be established at the UR-2 location if the total power is above 2500 MW for 50 ms. The alarm
is to be cleared if the power is below 2000 MW for 1 second.
The following settings and conditions are given.
•
UR-1: Nominal system voltage = 345 kV, SRC 1 CT ratio = 2000:5, Normal load current = 1.8 kA
•
UR-2: Nominal system voltage = 220 kV, SRC 4 CT ratio = 3000:5, Normal load current = 2.5 kA
The application requires the following features.
For UR-1: