CHAPTER 6: SETPOINTS
S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–103
Auxiliary overvoltage
The relay has one Auxiliary Overvoltage element per protection group. The element is
intended for monitoring overvoltage conditions of the auxiliary voltage input. A typical
application for this element is monitoring the zero sequence voltage (3V_0) from an open
corner Delta VT connection. The nominal voltage for the auxiliary voltage input is set under
Setpoints > S2 System Setup > Voltage Sensing > Aux VT Secondary
.
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 > S3 PROTECTION > SETPOINT GROUP 1(2) > AUXILIARY OV
AUX OV FUNCTION
Range: Disabled, Alarm, Latched Alarm, Trip
Default: Disabled
The selection of Latched Alarm, Alarm, or Trip setting enables the Auxiliary OV function.
The output relay #1 “Trip” will operate, if the function is selected as a Trip, and the
auxiliary voltage is above the AUX OV PKP setting for a time greater than the selected
AUX OV DELAY time. The “ALARM” LED will not turn on, if the auxiliary OV function is set to
Trip. The LED “ALARM” will flash upon an OV operating condition, with the aux. OV
function selected as Alarm, and will self-reset, when the operating condition clears. If
Latched Alarm is selected as an aux. OV function, the “ALARM” LED will flash during the
OV condition, and will stay “ON” after the condition clears until the reset command is
initiated. The output relay #1 “Trip” will not operate if the Latched Alarm or Alarm setting
is selected. Any or all of output relays 3 to 6 can be selected to operate when the
auxiliary OV function is selected as Latched Alarm, Alarm, or Trip.
AUX OV PKP
Range: 0.00 to 1.25 x VT in steps of 0.01
Default: 1.25 x VT
This setting defines the auxiliary OV pickup level.
AUX OV DELAY
Range: 0.1 to 600.0 sec in steps of 0.1
Default: 2.0 s
This setting specifies the time delay before OV operation.
OUTPUT RELAY 3 to 6
Range: Do not operate, Operate
Default: Do not operate
Any or all of the output relays 3 to 6 can be selected to operate upon an Auxiliary OV
condition. The selection of relay outputs operation is available no matter whether
Latched Alarm, Alarm, or Trip function is selected.
BLOCK 1/2/3
Range: Off, Contact Input 1 to 10[8], Virtual Input 1 to 32, Remote Input 1 to 32, Logic
Element 1 to 16
Default: Off
Three blocking inputs are provided in the Auxiliary OV menu. One blocking input “high” is
enough to block the function. The available selections for each block include Contact
input, Virtual Input, Remote Input, or Logic Element.