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Intelligent CT
2

Intelligent CT

Intelligent CT

(OP)
Has anybody any idea how I can measure not only the current in the meter tails entering my house but also the direction? I have solar panels installed and need to measure power being exported but not imported.

RE: Intelligent CT

You could use a hall effect sensor, as the output changes polarity (relative to its quiescent point) corresponding to the current direction.

RE: Intelligent CT

Assuming the utility connection is AC, the concept of 'direction' is meaningless. If you want to measure the flow of power then you will also need to measure the voltage, and have a meter which can deal with the phase angle between voltage and current.

RE: Intelligent CT

Google "four quadrant power meter."

You can use a three-phase unit even if your load is single-phase.

Best to you,

Goober Dave

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RE: Intelligent CT

With simple devices, on single phase circuit, you need to measure voltage on two points at maxim distance possible to avoid very high accuracy meters; voltage difference will be small and sure depends of current imported/exported and cable resistance; comparing these voltages tell you power direction: if voltage in point near supplier is higer than voltage near loads, mean you import energy and vice-versa for reverse situation.

RE: Intelligent CT

Which way is the electric meter turing. The power company - by law - must reimburse you if you are adding to the grid. Not good enough - then follow the above...

RE: Intelligent CT

"...by law..."

Law is a function of location. Various locations will have widely differing rate tariffs (especially regarding how much they'll pay for consumer generated power [less, net, generous]).

With a modest solar panel installation and a normal (Westernized) lifestyle, one might never produce enough power to exceed one's own power requirements. The meter would always spin forward, just a bit slower.

Of course, if one has a multi-kw installation, hopefully the resultant shadow doesn't cause the electric heating bill to rise.

RE: Intelligent CT

Simple... Use the TED5000 energy meter. Simple to use, web based, inexpensive. They have a version for wind/solar generation. I don't have any generation, but I use one on my house and love it.

http://www.theenergydetective.com/shopping-help


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