ABB RET 541 Product Manual page 62

62
Transformer Terminal
Table 30: Protection functions
Types of fault IEEE Device No.
Earth-fault 87TN
87TN
Overload 49M/49G/49T
Negative phase- 46
seguence
46
Overvoltage/ 59
undervoltage
59
27
27
27, 47, 59
27, 47, 59
Overfrequency/ 81U/81O
underfrequency
81U/81O
81U/81O
81U/81O
81U/81O
Overexcitation 24
24
Additional func- 68
tions
60
RET 541, RET 543, RET 545
IEC Symbol Protection function
Io>
Stabilized restricted
earth-fault protection
Io>
Stabilized restricted
earth-fault protection
3 Three-phase thermal
protection for devices
(motors, generators and
transformers)
I > Negative phase-
2
seguence protection,
low-set stage
I >> Negative phase-
2
seguence protection,
high-set stage
3U> Three-phase
overvoltage, low-set
stage
3U>> Three-phase
overvoltage, high-set
stage
3U< Three-phase
undervoltage, low-set
stage
3U<< Three-phase
undervoltage, high-set
stage
U < Phase-sequence voltage
1
U > protection, stage 1
2
U >
1
U < Phase-sequence voltage
1
U > protection, stage 2
2
U >
1
f</f>, df/dt Underfrequency or
overfrequency, stage 1
(incl. rate of change)
f</f>, df/dt Underfrequency or
overfrequency, stage 2
(incl. rate of change)
f</f>, df/dt Underfrequency or
overfrequency, stage 3
(incl. rate of change)
f</f>, df/dt Underfrequency or
overfrequency, stage 4
(incl. rate of change)
f</f>, df/dt Underfrequency or
overfrequency, stage 5
(incl. rate of change)
U/f> Overexcitation protection,
low-set stage
U/f>> Overexcitation protection,
high-set stage
3I > Three-phase transformer
2f
inrush and motor start-up
current detector
FUSEF Fuse failure supervision
1MRS755543
Function block
code
REF4A
REF4B
TOL3Dev
NPS3Low
NPS3High
OV3Low
OV3High
UV3Low
UV3High
PSV3St1
PSV3St2
Freq1St1
Freq1St2
Freq1St3
Freq1St4
Freq1St5
OE1Low
OE1High
Inrush3
FuseFail