GE 745 Instruction Manual page 144

S4 ELEMENTS
5.6.3 Differential Element
5.6.3.1 Main menu
 DIFFERENTIAL [
5–48
• EDIT SETPOINT GROUP: Select the number of the
are to be viewed and/or edited via the front panel keypad or any of the
communication ports. Selecting "Active Group" selects the currently active setpoint
group for editing.
• GROUP 2(4) ACTIVATE SIGNAL: Select any logic input which, when asserted, will
(remotely) select SETPOINT GROUP 2(4)
overridden if a higher number setpoint group is activated using the
setpoint or another logic input.
GROUP
PATH: SETPOINTS S4 ELEMENTS


]  PERCENT
DIFFERENTIAL
 HARMONIC
MESSAGE
INHIBIT

ENERGIZATION [
MESSAGE
INHIBIT

5th HARM
MESSAGE
INHIBIT
This section contains the settings to configure the percent differential element, including
all associated harmonic inhibit features. The 745 provides three independent harmonic
inhibit features:
HARMONIC INHIBIT
2nd + 5th harmonic which is 'in-circuit' at all times;
changing the characteristics of the inhibit scheme during energization to improve
reliability; and
5TH HARM INHIBIT
harmonic only, allowing inhibiting the percent differential during intentional overexcitation
of the system.
SETPOINT GROUP
to be the active group. This selection will be
DIFFERENTIAL


[ ]
See page 5–49

[ ]
See page 5–52

]
See page 5–53

[ ]
See page 5–56
, which implements an inhibit scheme based on 2nd or
ENERGIZATION INHIBIT
, which implements an inhibit scheme based on 5th
745 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETPOINTS
whose settings
ACTIVE SETPOINT
, which allows