Siemens 7SA511 manual Carrier Transmission With Blocking Signal, Overreach Z1B Blocking

7SA511 Line Protection Relay Chapter 7

the opposite line end per the relay programming instructions given in Chapter 5, “Programming the Relay.” When delivered from the factory, the input for the circuit breaker auxiliary contact is INPUT 3, assigned to the function CB Aux Cont NO. Change the function mode from NO to NC if necessary (i.e., CB Aux. Cont NC). If the circuit breaker position input is asigned differently, change the mode accordingly.

d) Open the circuit breaker. Repeat these tests for the other line end.

Carrier Transmission With Blocking Signal

If overreaching transfer mode with blocking signal is used, an understanding between both line ends is necessary.

Prerequisite Settings

Addr. LCD Text

7804 TELEPROTEC.

2201 POTT MODE

2202 POTT MODE

Description

Type of pilot protection scheme

Turn the permissive overreach transfer scheme on and off

Mode of operation for permis- sive overreach transfer scheme

Setting

OVERREACH

ON

Z1B BLOCKING

Test Procedure

1.At the line end to be tested as sender, simulate a fault in reverse direction; at the other end, simulate a forward fault within zone Z1B but beyond the limit of Z1. Since the transmitter sends a blocking signal, the receiving protection must not trip, unless in a delayed zone, as long as blocking signal is transmitted. After switching off the reverse fault on the sending side, the receiving side remains blocked for the send prolongation T-SEND-PRL (address 2206) plus the transient blocking time T-TRANSBLO (address 2203) of the receiving side.

2.Repeat this test for the other transmission direction.

Carrier Transmission With Underreach Transfer Signal

With permissive underreach transfer trip (PUTT), an understanding between both line ends is necessary.

Prerequisite Settings

Addr.	LCD Text
7804	TELEPROTEC.
2101	PUTT MODE

Description

Type of pilot protection scheme

Turn the permissive underreach transfer scheme on and off

Setting

UNDERREACH

ON

Test Procedure

1. At the line end to be tested as sender, simulate a fault within zone Z1.

July 27, 1995 7-11