Detecting first recepticle on a circuit

[Rich Grise]

It seems I've learned something today. It sounds like you're describing an outlet and circuit breaker in one box.

So, when any outlet on the "output side" trips it, the whole string goes out? Does the first one still work? I.e., does it have two reset buttons?

Thanks, Rich

[Ken Taylor]

Not in any I've seen. The outlet with the protection circuit trips out, disconnecting its own load and allt he downstream ones.

Cheers.

Ken

[Nehmo]

The GFCI and duplex receptacle are combined in a discrete or single device. Inside of this device is the GFCI circuitry. The connecting slots for a plug and the downstream (labeled "load") connectors are _both_ downstream from the circuitry.

If the GFCI is tripped, everything goes off.

There *are* two buttons, but one is "test" and the other is "reset".

[Peter Bennett]

Not quite - it just has a GFCI trip, no overcurrent trip, so it does not replace a normal circuit breaker.

The GFCI outlet, and any outlets connected to its "load" terminals, will switch off on a fault (or test). There is a single reset button to restore power to the GFCI outlet and any downstream outlets.

[John Fields]

[cs_posting]

Well, if you had a fast scope, and a pulse generator, and pulled the end out of the breaker box and drove it like an RF transmission line, you might learn something by plugging a simple "nightlight" load into each outlet while watching the scope.

If it's on the first floor and the basement is unfinished, you might be able to get a good idea just by looking up.

[Joe Soap]

In response to what posted in news: [e-mail]:

Or maybe use a Time Domain Reflectometer.

[holycow]

Connect the recepticle to your testicle and you will know !!!! :)

[David Combs]

And just what is that, and what does it do?

Thanks,

David

[Jeff]

Plug a large load like a hair blower into the plug, turn on and measure the voltage with a digital voltmeter. Plug with highest voltage should be the first.

[Joe Soap]

In response to what Jeff posted in news:4H%Rf.566845 $ [e-mail]:

If you type "Time Domain Reflectometer" into the Googlebox, and hit Return, all will be revealed.

[Tomi Holger Engdahl]

[e-mail] (David Combs) writes:

From

Time Domain Reflectometry measurements (sometimes called Time Domain Spectroscopy techniques) work by injecting a short duration fast rise time pulse into the cable under test. The effect on the cable is measured with an oscilloscope. The injected pulse radiates down the cable and at the point where the cable ends some portion of the signal pulse is reflected back to the injection point. The amount of the reflected energy is a function of the condition at the end of the cable. If the cable is in an open condition the energy pulse reflected back is a significant portion of the injected signal in the same polarity as the injected pulse. If the end of the cable is shorted to ground or to the return cable, the energy reflected is in the opposite polarity to the injected signal. If the end of the cable is terminated into a resistor with a value matching the characteristic impedance of the cable, all of the injected energy will be absorbed by the terminating resistor and no reflection will be generated. Should the cable be terminated by some value different from the characteristic impedance of the cable the amount of energy reflected back to the cable start point would be the portion of the pulse not absorbed by the termination. Also any change in the cable impedance due to a connection, major kink or other problem will generate a reflection in addition to the reflection from the end of the cable. By timing the delay between the original pulse and the reflection it is possible to discern the point on the cable length where an anomaly exists. The cable type governs this signal propagation speed. For example normal Category 5 cable propagation speed is 66% the speed of light, and for most coaxial cables this value is between 66% and 86%.

One circuit example for TDR signal generator: