Arc Fault Circuit Interrupter (AFCI)

Subject: Arc Fault Circuit Interrupter (AFCI) Compatibility

Arc fault circuit interrupters were developed to reduce the risk of fire due to series and parallel arc faults. Underwriters Laboratories published UL1699 – Standard for Safety for AFCIs – in 1996 to cover a wide variety of conditions to evaluate an AFCI. The standard includes requirements for the following conditions:

  • • Humidity
  • • Leakage Current
  • • Dielectric Strength Testing
  • • Abnormal Power Conditions
  • • Arc-Fault Detection
  • • Operation Inhibition
  • • Resistance to Environmental Noise
  • • Abnormal Operation
  • • Unwanted Tripping

Unwanted, or nuisance tripping is one of the biggest concerns for lighting systems designers.

UL defines four varieties of tests related to an AFCI’s ability to resist unwanted tripping.

  • • Inrush Current: High current draw devices such as capacitive systems, tungsten filament lamps and capacitor start motors.
  • • Normal Arcing: Normal household switches and appliance plugs, brush motors, thermostatic contacts.
  • • Non-Sinusoidal Waveforms: Electronic lamp dimmers and transformers, computer switching-mode power supplies and
    fluorescent lamps.
  • • Cross Talk: This test measures trip avoidance for an AFCI when an arc is detected in an adjacent circuit. Only the circuit with the arc should cause the breaker to trip, not another circuit.

Of these the most likely problem category for compatibility with electronic transformer and HID products is inrush current.

Hatch Transformers has conducted testing on transformer and ballast products and found that arc fault circuit interrupters are generally immune to nuisance tripping under normal startup conditions when used in combination with our products and wired in accordance with NEC guidelines. Although Hatch Transformers has conducted extensive laboratory testing, it is not possible to replicate and test every system design and field condition set. Hatch will assist customers should any tripping issues be encountered. This issue is not a failure of our product and therefore is not covered by our warranty. Please request a copy of our warranty document which can be sent to you by email.