NR Electric PCS-9611, Instruction Manual

Page: 43 / 300

3 Operation Theory
PCS-9611 Feeder Relay
3-7
Date: 2014-04-08
and IEEE Std C37.112-1996 standard).
p
p
T C
I I
k
t












1 ) / (

Where:
k = Constant, the setting [50/51Px.K] (x: 3 or 4).
α = Constant, the setting [50/51Px.Alpha] (x: 3 or 4).
C = Constant, the setting [50/51Px.C] (x: 3 or 4).
t = Operation time.
I = Measured phase current.
I
p
is the current threshold setting; the current setting of the stage x (x: 3 or 4) overcurrent
[50/51Px.I_Set] (x: 3 or 4) is used as the I
p
in this relay. If the stage x (x: 3 or 4) overcurrent
protection is used as IDMT overcurrent protection, the range of the setting [50/51Px.I_Set] (x:
3 or 4) is 0.05×In ~ 4×In.
T
p
is the time multiplier setting; the multiplier setting of the IDMT overcurrent protection
[50/51Px.TMS] (x: 3 or 4) is used as T
p
in this relay. If the stage x (x: 3 or 4) overcurrent
protection is used as IDMT overcurrent protection, the range of the setting [50/51Px.TMS] (x:
3 or 4) is 0.05 ~ 100.00.
Some recommended types of IDMT characteristic curves are applied in this relay. It is also can be
programmed according to the demand of the special practical application through the
PCS-Explorer configuration tool auxiliary software.
The setting [50/51Px.Opt_Curve] (x: 3 or 4) can be used to select the expected curve.
Setting Value Standard Time Characteristic k
α
C
0 Definite Time × × ×
1 IEC Standard Inverse 0.14 0.02 0.00
2 IEC Very Inverse 13.5 1.00 0.00
3 IEC Extremely In verse 80.0 2.00 0.00
4 IEC Short Time Inverse 0.05 0.04 0.00
5 IEC Long Time Inverse 120.0 1.00 0.00
6 IEEE (ANSI) Extremely In verse 28.20 2.00 0.1217
7 IEEE (ANSI) Very Inverse 19.61 2.00 0.491
8 IEEE (ANSI) Inverse 0.0086 0.02 0.0185
9 IEEE (ANSI) Moderately In verse 0.0515 0.02 0.114
10 IEEE (ANSI) Long Time Extremely Inverse 64.07 2.00 0.25
11 IEEE (ANSI) Long Time Very In verse 28.55 2.00 0.712
12 IEEE (ANSI) Long Time Inverse 0.086 0.02 0.185
13 User Programmable