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Fluke ST120+ GFCI Socket Tester with Beeper

Save 9%
Original price $21.99
Current price $19.99
SKU 5510334
Currently 24 in stock.

Fluke ST120+ GFCI Socket Tester with Beeper

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Fluke ST120+ GFCI Socket Tester with Beeper

The Fluke ST120+ GFCI Socket Tester with Beeper checks that each wire in the outlet is properly connected to the building's electrical system. Via the bright LEDs and included chart, you can quickly and easily verify the wiring of an outlet. Able to identify several common wiring errors, including reversed phase and neutral wires and an open ground, the ST120+ will give you confidence on your next job.

Audible alert helps you work faster, safer

The ST120+ also gives you a unique audible alert anytime voltage is detected. Save time when trying to identify which circuit breaker is connect to which outlet. Just plug the socket tester in, walk to the circuit breaker panel, and listen for the beeper to turn off – or on – as you flip the breakers. Once it does, you’ve found the correct breaker. Time – and trips – saved.
When switched on, the integrated beeper can also alert you to hazardous voltage at the outlet, even if the wiring is incorrect. Working in an office, hospital or other location where you don’t want to interrupt others? No problem – the beeper can be switched off.

One-button GFCI tests

The included GFCI test button on the ST120+ Socket Tester allows you to also test the operation of GFCI outlets. With a single push, the ST120+ can verify the operation of your GFCI equipped outlet. If the GFCI trips as expected, perfect, you can move on. If not, it’s time to take a closer look.

Fast visual identification of all 6 wiring conditions

The ST120+ has three bright, easy-to-see LED indicators.  This lets you see, at a glance, one of six wiring scenarios:

  • Correct installation
  • Open ground
  • Open neutral
  • Open hot
  • Hot/neutral reversed
  • Hot/ground reversed


      Rated operating Voltage: 110 - 125 V AC
      Wattage: 0.3 W
      Frequency: 50/60 Hz
      Integrated, switchable beeper: Yes
      GFCI test: Yes
      Indicator lights: 1 red, 2 green LEDs
      Rating: CAT III 300 V
      Warranty: Two years


      ST120 - Instruction Card

      ST120 - Data Sheet