ABB RELION REX640 - Page 1170

Value of setting CB
failure mode
Value of setting CB
failure trip mode
Conditions for activating Backup trip logic
• Two or three phase currents exceed Cur-
rent value setting.
Breaker status
1 out of 3
1 out of 4
2 out of 4
CB is in closed position.
Both(AND) 1 out of 3 CB is in closed position and any phase cur-
rent exceeds Current value setting.
1 out of 4 CB is in closed position and either of the fol-
lowing is true:
• Any phase current exceeds Current value
setting.
• The residual current exceeds Current val-
ue Res setting.
2 out of 4 CB is in closed position and either of the fol-
lowing is true:
• Any phase current exceeds Current value
setting and the residual current exceeds
Current value Res setting.
• Two or three phase currents exceed Cur-
rent value setting.
Both(OR) 1 out of 3 Either of the following is true:
• CB is in closed position.
• Any phase current exceeds Current value
setting.
1 out of 4 One of the following is true:
• CB is in closed position.
• Any phase current exceeds Current value
setting.
• The residual current exceeds Current val-
ue Res setting.
2 out of 4 One of the following is true:
• CB is in closed position.
• Any phase current exceeds Current value
setting and the residual current exceeds
Current value Res setting.
• Two or three phase currents exceed Cur-
rent value setting.
Once activated, TRBU remains active until the set Trip pulse time or until the reasons
for activation are reset. TRRET is also reset if BLOCK is activated.
In most applications, "1 out of 3" is sufficient.
Protection related functions 1MRS759142 F
1170 REX640
Technical Manual