GE D90 Plus Instruction Manual page 411

CHAPTER 8: AUTOMATION
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Step-Up Mode
Range: Time-out, Acknowledge
Default: Time-out
This setting defines the selector mode of operation. When set to "Time-out", the selector
will change its position after a pre-defined period of inactivity at the control input. The
change is automatic and does not require any explicit confirmation of the intent to
change the selector's position. When set to "Acknowledge", the selector will change its
position only after the intent is confirmed through a separate acknowledging signal. If
the acknowledging signal does not appear within a pre-defined period of time, the
selector does not accept the change and an alarm is established by setting the
output FlexLogic™ operand for 3 seconds.
STP ALARM
Acknowledge
Range: any automation logic operand or shared operand
Default: OFF
This setting selects an acknowledging input for the stepping up control input. The pre-
selected position is applied on the rising edge of the assigned operand. This setting is
active only under the acknowledge mode of operation. The acknowledging signal must
appear within the time defined by the
control input. A user-programmable pushbutton is typically configured as the
acknowledging input.
3-Bit A0, 3-Bit A1, 3-Bit A2
Range: any automation logic operand or shared operand
Default: OFF
These settings specify a three-bit control input of the selector. The three-bit control word
pre-selects the position using the following encoding convention.
Table 31: Selector switch three-bit control word
A2 A1
0 0
0 0
0 1
0 1
1 0
1 0
1 1
1 1
The rest position (0, 0, 0) does not generate an action and is intended for situations when
the device generating the three-bit control word is having a problem. When in time-out
mode, the pre-selected position is applied in the time specified (in seconds) by the
setting after the last activity of the three-bit input. When in acknowledge mode,
Timeout
the pre-selected position is applied on the rising edge of the acknowledging input
specified by the
3-Bit Acknowledge
The stepping up control input (selected by the
inputs (A0, A1, and A2) lock-out mutually. Once the stepping up sequence is initiated, the
three-bit control input is inactive; once the three-bit control sequence is initiated, the
stepping up input is inactive.
setting after the last activity of the
Timeout
A0
0
1
0
1
0
1
0
1
setting.
setting) and the three-bit control
Step-Up
AUTOMATION CONTROL
SELECTOR
Position
rest
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2
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