Arc Flash Protection - GE 350-A9 Instruction Manual

CHAPTER 6: SETPOINTS

Arc flash protection

NOTE:
NOTE:
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
The Arc Flash Protection module supports fast and secure protection against an arc flash
event for a safe working environment.
Arc Flash protection utilizes a total of four light detection fiber sensors and dedicated high-
speed instantaneous overcurrent element with secure Finite Response Filtering. Light from
the light sensor AND logic with high-speed overcurrent ensures fast and secure operation.
Further enhancement includes continuous monitoring of individual light sensors with self-
test trouble indication. Four Arc Flash elements with self-test from the individual light
sensors can be used to design flexible Arc Flash protection schemes for different
configurations depending upon the physical locations of the sensors. Each individual
element can also provide a higher level of redundancy/reliability of the system.
In case any issues with the sensors are detected (i.e. failure of a self-test), the
corresponding light sensor trouble operands ("LightSns# Trbl" and "LightSns Trbl") are
asserted. Very fast detection of the Arc flash light event is also possible using light as the
only detection parameter for alarm purposes. In addition, a user can design customized
logic using individual "Light Sensor # OP" operands from different light sensors.
Arc Flash protection should be connected to the SSR outputs (AUX5 and AUX6). If
connected to other outputs using logic elements, the total element operating time
increases by 8 ms plus the logic element protection cycle timer.
Path:
Setpoints > S4 Controls > Arc Flash
FUNCTION
Range: Disabled, Trip, Alarm, Latched Alarm, Control
Default: Disabled
The selection of Trip, Alarm, Latched Alarm or Configurable setting enables the HS
Phase/Ground IOC function.
HS PHASE PKP
Range: 0.05 to 30.00 x CT in steps of 0.01 x CT
Default: 2.00 x CT
The Light sensor is supervised by the high-speed overcurrent function, based on a fast
RMS measurement updated every 1/8 of power cycle. In order to permit the arc flash
function to trip, at least one HS Phase current value must be higher that this setpoint.
HS GROUND PKP / HS SENS GROUND PKP
Range: 0.05 to 30.00 x CT in steps of 0.01 x CT
Default: 1.00 x CT
Range: 0.005 to 3.000 x CT in steps of 0.001 x CT
Default: 0.100 x CT
The Light sensor is supervised by the high-speed overcurrent function, based on a fast
RMS measurement updated every 1/8 of power cycle. In order to permit the arc flash
function to trip, at least one HS Ground value must be higher that this setpoint.
The value of HS Gnd PICKUP can be set to a very high value, when only the HS Phs element
needs to be applied for Arc Flash detection.
LIGHT SENSOR 1(4)
Range: Disabled, Enabled
Default: 0.01 s
This setting indicates which sensors have been connected. The internal self-test logic
includes all enabled sensors when checking for sensor failure; sensors not in use should
be set to Disabled.
S4 CONTROLS
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