Logic Elements - GE SR345 Instruction Manual

S4 CONTROLS

Logic elements

6–112
Courtesy of NationalSwitchgear.com
Figure 35: Virtual inputs scheme logic
SETPOINT
V INPUT FUNCTION
Disabled = 0
Enabled = 1
"Virtual Input 1 to ON = 1"
From
Control
menu
"Virtual Input 1 to OFF = 0"
SETPOINT
V INPUT 1 TYPE
Latched
Self-Reset
The 345 relay has 16 Logic Elements available to build simple logic using the state of any
programmed contact, virtual, or remote input, or from the output operand of a protection,
or control element. Changing the state of any of the assigned inputs used as trigger
sources, will change the state of the Logic Element, unless a blocking input is present. The
logic provides for assigning up to three triggering inputs in an "OR" gate for Logic Element
operation, and up to three blocking inputs in an "OR" gate for defining the block signal.
Pickup and dropout timers are available for delaying Logic Element operation and drop-
out respectively. In addition, the user can define whether to use the "ON", or "OFF" state of
the programmed element by selecting ASSERTED: "On" or "Off".
Referring to the Logic Element logic diagram below, the Logic Element can be set to one of
four functions: Control, Alarm, Latched Alarm, or Trip. The Trip output relay will be
triggered when Trip is selected as a function, and the Logic element operates. Output relay
#1 (Trip) will not be triggered during Logic Element operation if Alarm, Latched Alarm, or
Control is selected.
The "PICKUP" LED will turn on upon a Logic Element pickup condition except when the
Logic Element function is selected as Control.
The "ALARM" LED will turn on upon Logic Element operation if the Logic Element function
selected is either Alarm, or Latched Alarm.
The "TRIP" LED will turn on upon Logic Element operation if the Logic Element function is
selected as Trip.
The option to trigger auxiliary output relays is provided for any of the selected Logic
Element functions.
The following path is available using the keypad. For instructions on how to use the
keypad, please refer to Chapter 3 - Working with the Keypad.
PATH:
SETPOINTS > S4 CONTROLS > S4 LOGIC ELEMENTS
LE1(16) FUNCTION
Range: Disabled, Control, Alarm, Latched Alarm, Trip
Default: Disabled
This setting defines the use of the Logic Element. When Trip is selected as a function, the
Logic Element will trigger Output Relay # 1 (Trip) upon operation.
S
LATCH
R
345 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 6: SETPOINTS
ACTUAL VALUES
V INPUT 1 NAME:
(Operand)
V Input 1 Status
897774.cdr