7SA511 Line Protection Relay

Acceptance Tests

V 70

60

V(Iph>>)

50

V(Iph>)

40

30

20

10

Pickup

Iph>

0

0

1

2

Iph>>

3

I/IN

Figure 3-1. Voltage-Controlled Overcurrent Fault Detector Characteristic.

Prerequisite Setting Addr. LCD Text

7802

DIST.F.DET

Description

Select the type of fault detection system

Setting

U/I

Test Procedure

1.Set test voltage to 0 V.

2.Slowly increase test current of one phase until the fault detector picks up. Pickup should occur when the test current exceeds the setting value Iph> (address 1611, factory preset is

0.2IN). With factory preset I/O configuration, the following LEDs should light at pickup:

LED 2 for phase 1

￿LED 3 for phase 2 LED 4 for phase 3

3.Switch off test current.

4.Using a phase-to-ground input voltage, set test voltage of the tested phase to approximately the rated phase-to-ground voltage (factory preset is VN SECOND/1.73 = 58 V). Set the test current of the same phase to twice the value of the minimum fault detection current IPH> at address 1611 (factory preset is 0.20IN).

5.Slowly decrease voltage until the fault detector picks up. Pickup occurs when the test voltage goes below the set value of addresses 1612 and 1613 (factory preset for both is 48 V). With factory preset I/O configuration the following LEDs will light for the tested phase.

LED 2 for phase 1

￿LED 3 for phase 2 LED 4 for phase 3

3-18

July 27, 1995

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Siemens 7SA511 manual Voltage-Controlled Overcurrent Fault Detector Characteristic, Prerequisite Setting Addr. LCD Text