CHAPTER 4: SETPOINTS
PROTECTION
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
4–183
FLEXCURVES
The custom FlexCurves are described in detail in the FlexCurves section of this chapter. The
curve shapes for the FlexCurves are derived from the formulae:
Where:
T = operate time (in seconds),
TDM = Multiplier setting,
I = input current,
I
pickup
= Pickup Current setting,
T
RESET
= reset time in seconds (assuming energy capacity is 100% and RESET is
“Timed”)
DEFINITE TIME CURVES
The Definite Time curve shape operates as soon as the Pickup level is exceeded for a
specified period of time. The base Definite Time curve delay is in seconds. The curve
multiplier of 0.05 to 600 makes this delay adjustable from 50 to 600000 milliseconds.
Where:
T = operate time (in seconds)
TDM = Multiplier setting
I = input current
I
pickup
= Pickup Current setting
T
RESET
= reset time in seconds (assuming energy capacity is 100% and RESET is
“Timed”)
Percent of Load-To-
Trip
The Percent of Load-to-Trip is calculated from the phase with the highest current reading.
It is the ratio of this current to the lowest pickup setting among the phase time and the
instantaneous overcurrent elements. If all of these elements are disabled, the value
displayed is “0”.
Summary of Contents for 869
Page 10: ...VIII 869 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL ...
Page 127: ...CHAPTER 3 INTERFACES SOFTWARE INTERFACE 869 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL 3 49 ...
Page 129: ...CHAPTER 3 INTERFACES SOFTWARE INTERFACE 869 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL 3 51 ...
Page 538: ...4 406 869 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL TESTING CHAPTER 4 SETPOINTS ...
Page 578: ...6 22 869 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL FLEXELEMENTS CHAPTER 6 METERING ...
Page 592: ...7 14 869 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL CLEAR RECORDS CHAPTER 7 RECORDS ...