ABB RED615 - Page 79

Two thermal overload protection functions are incorporated, one with one time
constant T1PTTR1 and other with two time constants T2PTTR1 for detecting
overloads under varying load conditions. The BLK_CLOSE output of the function is
used to block the closing operation of circuit breaker.
T1PTTR1
BLK_OPR
ENA_MULT
TEMP_AMB
OPERATE
START
ALARM
BLK_CLOSE
T2PTTR1
BLOCK
TEMP_AMB
OPERATE
START
ALARM
BLK_CLOSE
T1PTTR1_BLK_C LOSE
T2PTTR1_BLK_C LOSE
T1PTTR1_OPERATE
T2PTTR1_OPERATE
T1PTTR1_START
T2PTTR1_ALARM
T1PTTR1_ALARM
T2PTTR1_START
GUID-98DD8187-875F-4B44-977C-3B4097DE9D25 V1 EN
Figure 69: Thermal overcurrent protection function
Three overvoltage and undervoltage protection stages PHPTOV and PHPTUV offer
protection against abnormal phase voltage conditions. However, only two instances of
PHPTOV and PHPTUV are used in the configuration. Positive-sequence
undervoltage PSPTUV and negative-sequence overvoltage NSPTOV protection
functions enable voltage-based unbalance protection. A failure in the voltage
measuring circuit is detected by the fuse failure function and the activation is
connected to block undervoltage protection functions and voltage based unbalance
protection functions to avoid faulty tripping.
PHPTOV1
BLOCK OPERATE
START
PHPTOV2
BLOCK
OPERATE
START
OR
B1
B2
O
PHPTOV1_OPERATE
PHPTOV1_OPERATE
PHPTOV2_OPERATE
PHPTOV2_OPERATE
PHPTOV_OPERATE
PHPTOV1_START
PHPTOV2_START
GUID-9C062068-BF92-419D-BF9B-23F1CADE7444 V2 EN
Figure 70: Overvoltage protection function
1MRS758127 C Section 3
RED615 standard configurations
RED615 73
Application Manual