Horrible!! Absolutely does not work. I have another make of circuit tracer that cost maybe $20 more and it works great. I left it home and am working out of town so, I ordered this on, thinking it should be fine. Not so, terrible product, doesn't even reliably pick up the tone standing right next to it.

To say the least my husband was so excited about this and I have to admit that I was pretty stoked too! No more having to stand 2 floor up yelling down to my husband when he found the right switch. It works!!

I've found the following to be helpful when doing a scan, overall it is a very simple process.When you scan through all the breakers on the panel from left column down then to right column, please hold down the trigger (calibration) button and “don’t let go”. Then scan maybe even three rounds, left column, right column, left column… right…, until “NOT even one breaker makes a beeping sound”. This means calibration is “complete”.Let go of the trigger button, then simply pointing it to the breakers on the panels individually one by one “without pressing” the trigger button, one or two will sound. So look at the painted black arrow near the top of the unit, it will point to the right one; you can also lift the unit a bit above the breakers, so it beeps even better. Then as you turn the breaker in question off, the sound will stop. If it doesn’t, it is the adjacent breaker.When operating AC power outlets, use extra caution.*I’ve found that one outlet within a few feet of the breaker panel is an exception, not sounding for some reason. But other rooms are fine.

I would not rely on this detector. The signal pick up between breakers is suspect The good news is the audible plug-in can be heard at a distance in the house and confirms that I have turned on or off the circuit

Easy to use and works quite well.

Pour retrouver la fonction de chaque disjoncteur et l’identifier

Since Amazon often mixes products, this review is on the Sperry Instruments CS550A Circuit Breaker Finder. I understand Sperry's paper conservation efforts but they really should include a little something more in the package to avoid all the 1-star reviews.While some tools calibrate automatically, you have to calibrate the CS550A manually. With the transmitter plugged into an outlet (or light socket adapter ASIN: B002DN6QX2) and the pistol grip receiver switched on and trigger firmly held in, slowly pass over the center of breakers top to bottom, left column, then right, until there's no more beeping from the receiver. This takes mostly two passes but sometimes just 1 or even 3. Then, release the trigger and slowly scan over the center of the breakers again with the trigger released. Don't be tempted to pull the trigger during the final scan! The black arrow will point to the correct breaker. A really handy feature is you can turn the breaker off and listen for absence of the transmitter beep to verify you have located the correct breaker.Using this procedure, I got NO false positives and the tool (with one exception) always identified the correct breaker. Often I had a hard time believing the tool, however, by actually turning off the identified breakers and listening for the absence of the transmitter beep to verify, I located a total of 8 mislabeled breakers out of 24! Great job electrician and shame on the city inspector. No wonder I was so confused every time I worked on something electrical!The one breaker the tool had trouble identifying was the one I was most interested in identifying. I guess I've now identified what's on it by process of elimination! This circuit has a home theater, a TV, a cable modem, a WiFi router, a VOIP box, 2 network switches, an HDHomeRun tuner, 4 Western Digital NAS drives, a Synology NAS drive, a remote start fireplace, ceiling lights, nook light, porch light, and several wall outlets with fans plugged in. The tool did identify this breaker from the nook & porch lights and from the outlets located furthest from the electronics. I'm sure it would have done better if I'd have wanted to shut down the NAS drives but then I'd hoped to avoid that by purchasing the tool.Observations:1) The tool has trouble with heavily loaded circuits. Unplug heavy loads (fans, heaters, hairdryers, etc.) and turn off any incandescent lights that might also be on the same circuit you're testing.2) The tool seems to remember the previous calibration setting. You have to turn it off and recalibrate each time you move the transmitter.3) The tool seems to remember the previous calibration settings even if you just flick the power off and back on. It works best if you switch it off, go move the transmitter, switch back on, and recalibrate.4) OK, it's cheap plastic and you have to furnish your own 9v battery but it cost just over $20 and it works great!

Works like a charm. I would suggest watching YouTube clips on how it is used.

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