ABB RELION REX640 Technical Manual page 1080

Section 5
Protection related functions
1074
Value of setting CB Value of setting CB
failure mode failure trip mode
Breaker status 1 out of 3
1 out of 4
2 out of 4
Both(AND) 1 out of 3
1 out of 4
2 out of 4
Both(OR) 1 out of 3
1 out of 4
2 out of 4
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.
Conditions for activating Backup trip logic
CB is in closed position.
CB is in closed position and any phase current
Current value setting.
exceeds
CB is in closed position and either of the following
is true:
• Any phase current exceeds
setting.
• The residual current exceeds
Res setting.
CB is in closed position and either of the following
is true:
• Any phase current exceeds
setting and the residual current exceeds
Current value Res setting.
• Two or three phase currents exceed
value setting.
Either of the following is true:
• CB is in closed position.
• Any phase current exceeds
setting.
One of the following is true:
• CB is in closed position.
• Any phase current exceeds
setting.
• The residual current exceeds
Res setting.
One of the following is true:
• CB is in closed position.
• Any phase current exceeds
setting and the residual current exceeds
Current value Res setting.
• Two or three phase currents exceed
value setting.
1MRS759142 C
Current value
Current value
Current value
Current
Current value
Current value
Current value
Current value
Current
REX640
Technical Manual