Download Print this page

Undervoltage Element; Neutral Voltage Element; Nps Overvoltage Element; Overfrequency Element - Siemens Argus 8 7SG11 Manual

Voltage and frequency relays

Advertisement

6.2 Undervoltage Element

Undervoltage Element
Operate Level
Reset Level
Operate Time (see Fig.2)
1.1x to 0.9x setting
Reset Time
0V to 1.1x setting
0V to 2x setting

6.3 Neutral Voltage Element

Neutral Voltage Element
Operate Level
Reset Level
Operate Time
0V to 2x setting
0V to 1.1x setting
Reset Time
1.1x to 0.9x setting
1.1x to 0V
1
– For NVD settings below 7.5V the Reset Level can be up to 60% of operate value.

6.4 NPS Overvoltage Element

Negative Phase Sequence Element
Operate Level
Reset Level
Operate Time
0V to 2x setting
0V to 1.1x setting
Reset Time
1.1x to 0.9x setting
1.1x to 0V
2
– For NPS settings below 3.5V the Reset Level can be up to 80% of operate value.

6.5 Overfrequency Element

Overfrequency Element
Operate Level
Reset Level
Operate Time
For ROCOF between 0.1-10 Hz/sec
©2010 Siemens Protection Devices Limited
7SG11 Argus 8 Performance Specification
Setting ± 1% or 0.25V
≤ (operate level + hysteresis setting)
≤ 65ms
≤ 75ms
≤ 65ms
Setting ± 1% or 0.25V
1
> 95% of operate value
≤ 85ms
≤ 85ms
≤ 80ms
≤ 70ms
Setting ± 1% or 0.25V
2
> 95% of operate value
≤ 85ms
≤ 85ms
≤ 80ms
≤ 70ms
Setting ± 10mHz
Operate – 20mHz
Typically < 140ms
Maximum < 175ms
Typically < 100ms : AG8 - 300 series only
Maximum < 150ms
Chapter 2 Page 5 of 9

Advertisement

loading