GE 869 - Page 268

4–136 869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
PROTECTION CHAPTER 4: SETPOINTS
Figure 4-46: Voltage Dependent Overload Curve Selection logic diagram
89$1.cdr
OR
AN D AN D ANDANDAND AN DAN DANDAN D
Voltage dependent
motor curve
SETPOINTS
Motor
FlexCurve
CURVE:
SETPOINTS
Disabled = 0
Enabled = 1
VOLTAGE DEPENDENT FUNCTION:
SETPOINTS
= Off
VOLTAGE DEPENDENT VOLTAGE LOSS:
Vmin
Voltage Dependent Min Motor Volts :
SETPOINTS
%
110min
VVV 
%110
VV 
min
V < V
FLEXLOGIC OPERAND
MOTOR RUNNING
FLEXLOGIC OPERAND
MOTOR OVERLOAD
FLEXLOGIC OPERAND
MOTOR STARTING
FlexCurve Motor curve
Voltage dependent
FlexCurve
110% voltage locked rotor curve Minimum voltage locked rotor curve 100% voltage locked rotor curve
2
5
2 5
)(
I
tI
It


2
1
2
1
)(
I
tI
I
t


2
3
2
3
)(
I
tI
I
t


Vratio
Auxiliary VT Ratio :
Phase VT Ratio :
Phase Voltages
VA RMS VB RMS VC RMS
rated
ratioRMS
V
VV
V


SETPOINTS
Vrated
MOTOR NAMEPLATE VOLTAGE:
SETPOINTS
Select lowest value V
RMS
=min(V
AB
,V
BC
,V
CA
)
0.02530337
2116623.2TD



0.05054758 
()
1I()1
2
I
)( It
TO THERMAL
MODEL LOGIC on next page
FLEXLOGIC OPERAND
VFD NOT BYPASSED
AND