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Setting
The table below shows the setting elements necessary for the NOC protection and their setting
ranges.
Element
Range
NC1
0.5 – 10.0 A
(0.10 – 2.00 A)(*1)
TNC1P
0.010 – 1.500
(TMS)
TNC1D
0.00 – 300.00 s
TNC1RD
0.0 – 300.0 s
TNC1RP
0.010 – 1.500
(RTMS)
NC2
0.5 - 10.0 A
(0.10 – 2.00 A)(*1)
TNC2
0.00 – 300.00 s
[MNC1]
DT/IEC/IEEE/US/CON
[MNC1C]
MNC1C-IEC
NI / VI / EI / LTI
MNC1C-IEEE
MI / VI / EI
MNC1C-US
CO2 / CO8
[NC1R]
DEF / DEP (*2)
[NC1EN]
Off / On
[NC1-2F]
NA / BLK
[NC2EN]
Off / On
[NC2-2F]
NA / BLK
[APPL-CT]
3P / 2P / 1P
(*1) Current values shown in the parenthesis are in the case of a 1 A rating. Other current
values are in the case of a 5 A rating.
(*2) DEF: Instant or Definite time, DEP: Inverse time
Sensitive setting of NOC1 and NOC2 thresholds is restricted by the negative phase sequence
current normally present on the system. The negative phase sequence current is measured in the
relay continuously and displayed on the metering screen of the relay front panel along with the
maximum value. It is recommended to check the display at the commissioning stage and to set
NOC1 and NOC2 to 130 to 150% of the maximum value displayed.
The delay time setting TNC1 and TNC2 is added to the inherent delay of the measuring elements
NOC1 and NOC2. The minimum operating time of the NOC elements is around 200ms.
Step
Default
Remarks
0.1 A
2.0 A
NOC1 threshold setting.
(0.01 A)
(0.40 A)
0.001
1.000
NOC1-I time multiplier setting. Required if
[MNC1] = IEC, IEEE, US or CON.
0.01 s
1.00 s
NOC1-D definite time setting. Required if
[MNC1] = DT.
0.1 s
0.0 s
NOC1-I definite time delayed reset.
Required if [MNC1] = IEC or [NC1R] = DEF.
0.001
1.000
NOC1-I dependent time delayed reset time
multiplier. Required if [NC1R] = DEP.
0.1 A
1.0 A
NOC2 threshold setting.
(0.01 A)
(0.20 A)
0.01 s
1.00 s
NOC2 definite time setting
DT
NOC1 characteristic
NOC1-I inverse curve type.
NI
Required if [MNC1] = IEC.
MI
Required if [MNC1] = IEEE.
CO2
Required if [MNC1] = US.
DEF
NOC1-I reset characteristic. Required if
[MNC1] = IEEE, US or CON.
Off
NOC1 Enable
NA
Blocked by ICD
Off
NOC2 Enable
NA
Blocked by ICD
3P
Three-phase current input
⎯
⎯
35
6 F 2 S 0 8 4 2
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