GE M60 Instruction Manual page 385

CHAPTER 5: SETTINGS
NEUTRAL WIRE OPEN 1 DETECTION
connected in Delta, do not enable this function because there is no neutral wire for Delta connected VT.
NEUTRAL WIRE OPEN 1 3 HRAM PKP
logic to pick up.
DETECTION
Base voltage for this element is
of DELTA VTs. The setting is found under
SETTING
VA’, VB’ and VC’ are the
Function voltage magnitude of one
cycle before
Enabled = 1
SOURCE 1
VA
VB
VC
V_2
V_1
I_1
FLEXLOGIC OPERANDS
SRC1 50DD OP
OPEN POLE OP
The OPEN POLE OP operand applies
to the D60, L60, and L90
SETTING
Neutral Wire Open Detect
Enabled = 1
SOURCE 1
3V_0 (3rd Harmonic)
5.8.11.5 Broken rotor bar detection
SETTINGS  CONTROL ELEMENTS  MONITORING ELEMENTS  BROKEN ROTOR BAR
 BROKEN ROTOR BAR

M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
— Enables and disables the VT neutral wire open detection function. When the VT is
— Specifies the pickup level of 3rd harmonic of 3V0 signal for the
setting in the case of WYE VTs and (
PHASE VT SECONDARY
SETTINGS  SYSTEM SETUP  AC INPUTS  VOLTAGE BANK  PHASE VT SECONDARY
Figure 5-147: VT fuse fail logic
COMPARATORS
Run
|VA’|-|VA| > 0.2 pu
& |VA’| > 0.8 pu
Run
|VB’|-|VB| > 0.2 pu OR
& |VB’| > 0.8 pu
Run
|VC’|-|VC| > 0.2 pu
& |VC’| > 0.8 pu
Run
V_2 > 0.1 pu
OR
Run
V_1 < 0.05 pu
AND
Run
I_1 > 0.075 pu
Run
TIMER
V_1 < 0.80 pu
2 cycles
Run
AND
I_1 < 0.05 pu
AND
OR
AND
AND
SETTING
3 HARM PKP
Run
AND
3V_0 3rd Harm >setting
BROKEN ROTOR BAR

FUNCTION: Disabled
START OF BRB

OFFSET: 0.40 Hz
END OF BRB

OFFSET: 2.00 Hz
BRB START BLOCK

DELAY: 60.00 s
PHASE VT SECONDARY
OR
FUSE
FAIL
TIMER
2 cycles
SET
AND
0
Latch
20 cycles
TIMER
30 cycles
RESET
0
Reset-dominant
TIMER
5 cycles
AND
0
TIMER
0
AND 20 cycles
Range: Disabled, Enabled
Range: –12.00 to 11.99 Hz in steps of 0.01
Range: –11.99 to 12.00 Hz in steps of 0.01
Range: 0.00 to 600.00 s in steps of 0.01
CONTROL ELEMENTS
NEUTRAL WIRE OPEN
)/ in case
3
AND
FAULT
OR
FLEXLOGIC OPERANDS
SRC1 VT FUSE FAIL OP
SRC1 VT FUSE FAIL DPO
FLEXLOGIC OPERAND
SRC1 VT FUSE FAIL VOL LOSS
FLEXLOGIC OPERAND
OR
SRC1 VT NEU WIRE OPEN
FLEX-ANALOG
SRC1 3V0 3nd Harmonic
827093AQ.CDR
5-257
.
5