Schweitzer Engineering Laboratories SEL-700GT - Figure 4.105 Synchronism-Check Function Voltage Elements; Figure 4.106 Synchronism-Check Function Voltage Element Characteristic

4.155
Date Code 20170814 Instruction Manual SEL-700G Relay
Protection and Logic Functions
Group Settings (SET Command)
Figure 4.105 Synchronism-Check Function Voltage Elements
Figure 4.106 Synchronism-Check Function Voltage Element Characteristic
If your synchronization practice requires that the generator voltage be higher
than the system voltage prior to closing the generator breaker, set
GENV+ = Y. If not, set GENV+ = N.
Use the voltage ratio correction factor setting 25RCFX to compensate nominal
magnitude of the phase voltage (selected by the SYNCPX setting) to match
the nominal magnitude of the synchronism-check voltage VS. Many
59VPX
Relay
Word
Bits
59VSX
GENVHI
GENVLO
VDIFX
GENV+ = Y
25VDIFX
25VLOX
|VS|
|Vpxc|
25VHIX
E25X = Y
Settings
||VS| – |Vpxc|| / |VS| • 100%
Setting
Setting
Setting
+
_
+
_
+
_
+
_
+
_
+
_
BSYNCHX
Vpxc = 25RCFX * VP (where 25RCFX is the setting and VP is determined by the SYNCPX setting).
25VHI
25VLO
|VPc|
|VS|
Volts
Acceptable
Voltage
Window
Difference
Voltage
O
Note: V
DIFF
=
| | VS | – | VPc | |
| VS |
• 100%