CHAPTER 2: INSTALLATION
MECHANICAL INSTALLATION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
2–13
Arc flash sensors
Arc flash sensors house the fiber optics that are used to detect the arc flash. Mounting
details depend on the sensor type (point or loop).
For detailed installation, testing and maintenance guidance for Arc Flash sensors, see GET-
20057
3 Series Arc Flash Application Note
.
CAUTION:
If the relay is used in the computation for reducing the Hazard Reduction Category
code, operands for sensor failures must be assigned to an auxiliary output relay which
must be connected into the control logic of the breaker equipment to ensure safe
operations when the output relay is asserted. In the event of this assertion, the Hazard
Reduction Category code cannot be maintained unless backup protection is continuing
to maintain it.
CAUTION:
This product uses optical electronic devices (line or point sensors) to sense arc flash
fault conditions. It is recommended to follow proper housekeeping measures &
establish a regularly scheduled preventive maintenance routine to ensure proper
device operation. For maintenance recommendations, see GET-20057
3 Series Arc
Flash Application Note
Arc flash sensors are available in two different configurations, point and loop. Loop sensors
can be used with a black-coated sensor fiber extension to connect the ends of the loop
sensor to the 350 relay through panels up to 51 mm (2 inches) thick.
Tx
Rx
Duplex
Connector
Single
Connectors
Bulkhead
Connectors
Sensor Fiber
(length Y)
Loop Sensor (with Sensor Fiber Extension)
Tx
Rx
350 Relay
Single
Connectors
Sensor Fiber
(maximum length 70 m)
Loop Sensor
Tx
Rx
Duplex
Connector
Point Sensor
Assembly
Point Sensor
350 Relay
350 Relay
Duplex Sensor Fiber
(maximum length 35 m)
Duplex Sensor Fiber
(length X)
Sensor Fiber Extension
Total Sensor Fiber Length = 2 times(length X) + length Y
(maximum 70 m)
Single
Connectors