Thytronic Pro-N NVA100X-D

FUNCTION CHARACTERISTICS
173
NVA100X-D - Manual - 02 - 2016
Minimum power factor - 55
Preface
Two independent time adjustable thresholds with lag, lead or lag/lead programmable power factor.
For each elements can a consensus for start / trip operation may be set only if the circuit breaker is
closed and after an adjustable enabling time, the closure (tARM-cosphi<) .
Operation and settings
The power factor is computed:
± cos
ϕ = ± P / S
where:
P is the total active power: ± P = U
L1
· I
L1
· cos ϕ
L1
+ U
L2
· I
L2
· cos ϕ
L2
+ U
L3
· I
L3
· cos ϕ
L3
S is the total apparent power: S = √P
2
+ Q
2
The lag power factor (cos ϕ = P/S with Q ≥ 0) and the lead power factor are compared with the setting
value (cos
ϕ
lag
<, cos ϕ
lead
<).
—
•
•
-Q
G
lag
Q/2
Q
Q/2Q
cosG
G
lead
CPhi1<def CPhi1<def
NO TRIP NO TRIP
TRIP TRIP
+Q
+P
-P
TRIP
CPhi1<def
CPhi1<def
TRIP
TRIPTRIP
NO TRIP
NO TRIP
Tripping direction setting: CosPhi Lag/Lead
General operation characteristic for the out of step element - 55
-Q
G
lag
Q/2
Q
Q/2Q
cosG
G
lead
CPhi1<def
NO TRIP
TRIP
+Q
+P-P
TRIP
CPhi1<def
TRIP
NO TRIP
NO TRIPNO TRIP
Tripping direction setting: CosPhi Lag
General operation characteristic for the out of step element - 55
-Q
G
lag
Q/2
Q
Q/2Q
cosG
G
lead
CPhi1<def
NO TRIP
TRIP
+Q
+P-P
CPhi1<def
TRIPTRIP
NO TRIP
NO TRIP
NO TRIP
Tripping direction setting: CosPhi Lead
General operation characteristic for the out of step element - 55