Siemens Argus 7SR22 - Power Protection: Sensitive Power (32 S) - 7 SR22; Figure 3.18-1 Logic Diagram: Sensitive Power Protection (32 S)

7SR210 & 7SR220 Description of Operation
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3.18 Power Protection: Sensitive Power (32S) – 7SR22
Two under/over sensitive power elements are provided in the 7SR22 models. The elements can measure real,
reactive or apparent power.
Sensitive power functionality utilises the I
SEF
current input i.e. a single CT input is used. Balanced load conditions
are assumed. Any one of the three phase currents can be wired to the I
G
current input – the POWER PROT’N >
SENSITIVE POWER > Gn 32S Phase Selection setting is used to ensure that the correct power is measured.
Gn 32S-n Setting sets the pick-up power level for the element.
Under-power or over-power operation can be set by the Gn 32S-n Operation setting.
An output is given after elapse of the Gn 32S-n Delay setting.
Operation of the under/over power elements can be inhibited when:
The measured current is below the Gn 32S U/C Guard setting
A VT Fail condition is detected
Inhibit 32S-n A binary or virtual input.
V
1
V
2
V
3
Enabled
<
&
Gn 32S-n U/C
Guard Setting
Gn32S-n: Power: P, Q, R
Gn32S-n: Direction
Gn32S-n: Setting
Gn 32S-n U/C
Guard
I
SEF
32S CT Angle Comp
Gn 32S-n Delay
32S-n
General Pickup
En.
+W
-VAr
-W
-VAr
-W
+VAr
+W
+VAr
Enabled
Inhibit
VT Fail
&
Gn 32S-n VTS
Action
Gn 32S-n Element
Inhibit 32S-n
&
Gn32S: Phase Selection
Gn32S-n: Operation: Under/Over
Figure 3.18-1 Logic Diagram: Sensitive Power Protection (32S)