voltage is 120,circuit tester says all positions and correct . It will run a small .6 amp fan fine but a 2.1 amp box fan funs about 1/2 speed. My circular saw just grunts, no go. what is up?

  • Do other outlets on the circuit work fine?
    – Hart CO
    Aug 10, 2017 at 21:08
  • Check that the connections are tight on the receptacle and that any wire nut connections are tight. Shut the breaker off first.
    – ArchonOSX
    Aug 10, 2017 at 21:09
  • What kind of circuit tester are you using?
    – mmathis
    Aug 10, 2017 at 21:16
  • 1
    Does a light light up anywhere when you try to use the tool? Did a switch used to be, or is still, at that location? If it were in series with something, like several outside lights, that would explain everything. Aug 10, 2017 at 22:53
  • +1 on @Harper comment but if you get to the point of a light lighting up when the tool is used, just step away and call a professional immediately.
    – Jeffrey
    Dec 2, 2017 at 14:33

2 Answers 2


You mentionned the voltage being 120v. I assume this is when there is no load on the circuit.

Most likely, when you draw higher amperage, the voltage drops in a bad connection. This could be:

  • a bad backstab connection
  • a loose wire nut somewhere along the path from panel to outlet
  • a damaged wire somewhere in the path
  • way too long wiring (unlikely)

Since you're able to use a voltmeter to measure the 120v, you can also measure it while there's a load. (use something safer than a saw, if you're going to look at the voltmeter at the same time, say a toaster :-) )

Once you confirm the voltage drops, just walk back along the path, and figure out where the drop occurs. Either at the outlet backstab or at a loose nut would be my guess.

Fix it by redoing the nut correctly or not using the backstab.

Personnaly, if I'd trace it back all the way to the first connection after the panel, I'd call the electrician.


Sounds like back stabs they will supply enough current for a small load but a heavy load the connection starts arcing. This will cause a wiring failure over time. It may be that outlet or one before if daisy chained. I would be checking the outlets and probably replacing them if they are back stab only. I use the screw terminals because of this problem. It could be a bad wire or a bad connection at the panel but backstab problems are quite common.

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