Signals - ABB RELION REX640 Technical Manual

Section 5
Protection related functions
5.13.7
1182
This problem can be solved using the reverse directional residual overcurrent function
to recognize the fault in reverse direction and temporarily block the operation of the
scheme communication logic due to the current reversal condition. This is used in
RCRWPSCH.
Weak-end infeed (WEI) logic
Do not use the WEI function at both feeder ends. It can only be enabled
at the weak end.
The WEI logic is recommended to be used only in the permissive schemes.
Setting guidelines for current reversal logic
Reversal reset time: This setting can be set to the maximum reset time of the
communication channel. A minimum setting of 40 ms is recommended. A long
Reversal reset time setting increases the security against unwanted tripping, but
delays the fault clearing if the fault develops from one feeder to involve the other.
However, the probability of this type of fault is small.
Reversal time: Set the start delay reversal time below 80 percent of the breaker operate
time, but to a minimum of 20 ms.
Setting guidelines for Weak-end infeed (WEI) logic
The WEI logic returns the received carrier signal with the ECHO output when it
receives the carrier signal (CR) if no fault has been detected by the forward and reverse
directional measuring elements and the duration is longer than the Wei Crd time
coordination time delay setting. To prevent the spurious carrier receive signals from
activating the WEI logic and causing unwanted communication, the Wei Crd time
setting can be set to "0.010 s".

Signals

Table 1099: RCRWPSCH Input signals
Name Type
URES SIGNAL
BLOCK BOOLEAN
BLK_IRV BOOLEAN
BLK_WEI1 BOOLEAN
BLK_WEI2 BOOLEAN
IRV BOOLEAN
FF BOOLEAN
CB_OPEN BOOLEAN
CR BOOLEAN
CR BOOLEAN
Default Description
- Residual voltage
0=False Block signal for activating the blocking mode
0=False Block of current reversal function
0=False Block of WEI Logic
0=False Block of WEI logic due to operation of other
protections
0=False Activation of current reversal logic
0=False Block of trip from WEI logic through fuse-failure
function
0=False Block of trip from WEI logic by an open breaker
0=False POR Carrier receive for WEI logic
0=False POR Carrier signal received from remote end
1MRS759142 C
REX640
Technical Manual