Arc Flash Detection

Arcteq’s arc flash detection system consists of an arc flash relay, detection sensors and an arc quencher. The AQ100 series arc flash relay is an ultra-fast, highly accurate system. The AQ1000 arc quencher offers a ‘cure’ to arc faults, by drawing it away from the switchgear and extinguishing it. When combined with Arcteq’s detection sensors, this is a complete solution to arc flash detection.

What is an arc flash relay and an arc quencher?

An arc flash relay is partnered with a number of sensors. These sensors are located in each compartment, and will detect the arc fault through the detection of light or pressure. as soon as it starts to develop. The relay then sends a trip command (in just 2ms) to the circuit breaker nearest to the fault when an arc fault is detected. However, it’s important to take into consideration the additional (and often much longer) opening time of the circuit breaker.

The AQ1000 arc quencher is designed to facilitate for faster arc elimination. To do this, the AQ1000 creates a three-phase low impedance parallel path for the fault current, drawing the arc fault into the quenching unit, extinguishing the arc rather than letting it extend into the switchgear. Total operational time (to fully eliminate the arc) is just 3ms. This takes equipment and personnel outside the danger zone of 50ms – 100ms.

Fitting an AQ1000 quencher ensures your system sits at IEEE 1584 Hazard Risk Category 0. Category 0 is for equipment that poses very little risk, so PPE requirements are much lower.

Some of the key benefits of the Arcteq arc protection system are:

  • Fast trip command time of 2ms and arc elimination is just 3ms
  • Extremely flexible system with a large range of sensors and configuration options
  • Up to 12 point sensors available per relay ensuring all parts of the switchgear are being monitored
  • Panel/rack and din rail mounting available
  • 3 phase current detection
  • 3 different detection methods: current, pressure and light
  • The AQ1000 is the only reusable arc quencher on the market. This means your system can be immediately protected against arc faults immediately after the unit has been quickly reset.

The range of Arcteq arc flash detection sensors allows for a flexible configuration with different units and different switchgear types, depending on specific application requirements. Sensors available are arc point sensors and arc fibre sensors.

An arc flash relay works like a car bumper. In a road accident the bumper is sacrificed to prevent more expensive and extensive damage to the car. An arc protection relay limits an arc fault’s damage to a few components instead of an entire board or substation.

This video gives you further background on the AQ1000 quencher and how it fits with the other parts of the arc protection system:

Technical specifications

AQ100 series of arc flash relays:

  AQ110F AQ110P AQ102 AQ101 AQ101D AQ101S
Wide range power supply (18-72Vdc or 80-265Vac/dc) Yes Yes Yes Yes Yes Yes
Mounting Panel/rack Panel/rack Panel/rack Panel/rack Din rail Panel/rack
3 phase current detection (1/5A) Yes Yes
Residual current detection (1/5A) Yes Yes
Max number of point sensors 12 12 12 12
Max number of fibre loop sensors 3 1 (option) 3 1 (option) 1 (option)
High Speed Outputs (2ms trip time) 2 2
Number of trip relays (7ms trip time) 4* 4* 4* 4* 4* 3*
System failure relay 1 1 1 1 1 1
Binary outputs (24Vdc) 1 1 1 1 1 3
Binary inputs (24/110/220Vdc) 2 2 2 2 2 6
Push button Yes Yes Yes Yes Yes Yes
Non-volatile memory Yes Yes Yes Yes Yes Yes
Indication LEDs 20 20 12 12 12 17


AQ1000 arc quenching device:

Power Supply 80-265Vdc or 18-70Vdc
Rated Voltage 690V
Short-circuit withstand 50kA for 1 second, 75kA for 0.5 second, 100kA for 0.2 second
BIL 12kV
Peak Current 220kA
Mechanical life 100 open/close cycles
Electric life 2 operations
Binary inputs 4
Indication LEDs 13


Arc Flash Detection sensors available:

AQ 01 – Arc Light Point Sensor.
  • 8000Lux light intensity threshold.
  • 180 degrees detection radius.
  • IP64 mechanical protection.
  • Maximum three sensors series-connected.
  • Standard shielded twisted pair 0.75mm² wiring arrangement.
  • Maximum wire length 100 metres.
  • Operating temperature -20 to +85°C.
AQ 02/AQ03/AQ04 Arc Light and Pressure Sensor.
  • 3 wire (+24Vdc, Signal, Gnd).
  • Current based information (2mA, 20mA).
  • Maximum 3 sensors in line (up to 200m line).
  • Snap-in cable connector for quick installation.
  • Shielded cable connection.
  • IP 60 mechanical protection (AQ01C IP62).
  • EMC compatible with IEC60255-22-4 (Fast transient 4kV).
  • 1ms pick up for light and pressure (0.2bar increase).
AQ 06 – Arc Light Fibre Sensor (plastic).
  • Plastic fibre.
  • 8000Lux light intensity threshold.
  • 360 degrees detection radius.
  • 5cm bending radius.
  • Maximum fibre length 40 metres.
  • Operating temperature -40 to +85°C.
AQ 07 – Arc Light Fibre Sensor (glass).
  • Covered glass fibre.
  • 8000Lux light intensity threshold.
  • 360 degrees detection radius.
  • 1cm bending radius.
  • Maximum fibre length 50 metres.
  • Operating temperature -40 to +85°C.
AQ 08 – Arc Light Fibre Sensor (glass, high temperature).
  • Covered glass fibre.
  • 8000Lux light intensity threshold.
  • 360 degrees detection radius.
  • 1cm bending radius.
  • Maximum fibre length 40 metres.
  • Operating temperature -40 to +125°C.