4–394 869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
FLEXLOGIC CHAPTER 4: SETPOINTS
PICKUP
Range: -30.000 to 30.000 pu in steps of 0.001 pu
Default: 1.000
This setting specifies the operating threshold for the effective operating signal of the
element.
If the “Over” direction is set, the element picks up when the operating signal exceeds the
PICKUP value.
If the “Under” direction is set, the element picks up when the operating signal falls below
the PICKUP value.
The HYSTERESIS setting controls the element drop out.
Notice that both the operating signal and the pickup threshold can be negative when
facilitating applications such as reverse power alarms.
The FlexElement can be programmed to work with all analog values measured or
computed by the relay. The PICKUP setting is entered in pu values using the following
definitions of the base units:
Table 4-40: Definitions of the Base Unit for the FLEXELEMENT
Measured or calculated analog
value related to:
Base Unit
Voltage V
BASE
= maximum nominal primary RMS value of the Input
1(+) and input 2(-) inputs
Current I
BASE
= maximum nominal primary RMS value of the Input 1(+)
and input 2(-) inputs
Power P
BASE
= maximum value of V
BASE
* I
BASE
for the Input 1(+) and
input 2(-) inputs
Power Factor PF
BASE
= 1.00
Phase Angle DegBASE
= 360 deg
Harmonic Content H
BASE
= 100% of nominal
THD THD
BASE
= 100%
Frequency f
BASE
= nominal frequency as entered under the SYSTEM
SETUP menu
Volt/Hz BASE = 1.00
RTDs BASE = 1.00°C
I
2
t (arcing Amps) BASE = 2000 kA
2
*cycle
Current Unbalance BASE = 1.00%
Source Energy (Positive and Negative
Watthours, Positive and Negative
Varhours)
EBASE = 10000 MWh or MVAh, respectively
Differential and Restraint Currents
(Percent Differential)
I
BASE
= Primary of the CT with maximum primary current
rating
Thermal Capacity Used BASE = 1.00%
Thermal Lockout Time BASE = 10 minutes
Thermal Model Load and Biased
Motor Load
BASE = 1.00 pu of FLA
Trip Time on Overload BASE = 10 seconds
Impedance Z
BASE
= PhaseVTSecondary / PhaseCTSecondary, where
PhaseVTSecondary and PhaseCTSecondary are the
secondary nominal voltage and the secondary nominal
current of voltage and current bank to calculate the
impedance.
PhaseVTSecondary is specified in the setting under
Setpoints > System > Voltage Sensing, and
PhaseCTSecondary is determined by the order code.
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