Can you use this just communicate to a raspberry pi without the internet

I want to hook this to two lights that our about 40 feet in the air and have them send data a rasberry pi. I want to see how much energy both are using during the week. I love how the graph are on the cms. Any help would be great and what pieces to buy.

It would be helpful if you expanded your explanation a little, because my crystal ball is struggling to relate the title of the thread to two lights 40 feet in the air.

Answering the question in the title, an emonPi can operate as a self-contained unit, accessible via wi-fi.

Sorry about that. They lights are connect 40 feet on a wall. The box is two feet from the light. Inside the box has the ground and hot. The building does not have a wifi signal. I wanted to have each light to have a emonPi whichever one to connect directly to a rasPi with a screen to display the info about the lights.

Again sorry I hope this helped out a little bit more.

Tell me what you really want to achieve. How and where do you want to see the result of the measurements?

I want to measure the power consumption of two different lights. I want to display the information on my rasPi. The RasPi has a touch screen on it. I want to compare the two showing if one is consuming more power than the next over a given time. Like a month.

I think you need an emonTx mounted in the “box” that feeds the lights, or if it’s a metal box, in a (weatherproof? ) plastic box adjacent. You’ll need two CTs, to measure the current drawn by each light, and an ac adapter to measure the voltage and to supply the power. You will not be able to use our standard 100 A CT, even though you haven’t said what the current drawn by each lamp is likely to be, I am reasonably certain that it will not be sensitive enough to measure the current drawn by a single lamp. It will be necessary to find an alternative, more sensitive, CT.
The 10 A unit here is known to work with the emonTx, though you’ll need to change one resistor in each channel: and even then, I wouldn’t like to guarantee the accuracy below 100 mA (approx 12 W, assuming you’re on 120 V).
You will then need to add a RFM69Pi receiver board to your Raspberry Pi to enable it to receive the transmissions from the emonTx, and you can download emonCMS or purchase a pre-loaded SD card.

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Hi Otis,

I see you’re in Kentucky. Greetings from Oklahoma!

Are your lamps similar to the type used on utility poles? In other words, are they similar to a street lamp?



@Bill.Thomson they are more like factory lights.

By that do you mean something like the lamps in a gymnasium?

@Bill.Thomson Yeah I want to compare the power draw with those with some LED lights that are almost the same brightness

When you power them on, do they take a while to come up to full intensity, or ar they at full brilliance immediately?

@Bill.Thomson The ones I’m comparing them to do. But the led don’t. Just want to do a comparison on the two. and have the results display on my raspi. But they need to just communicate with the pi.

Otis estimates his present lamp load to be ~30A. From his description, (we exchanged a few PMs) it sounds like one of his lamps is a Mercury vapor, or low pressure Sodium unit

A single lamp, drawing ~30 A even at 120 V, represents a load of 3.6 kW. That’s a lot of light. The highest power single lamp that I could find on a trade website is 1000 W (SON - high pressure sodium), and the biggest mercury vapour is 250 W. So even allowing for losses in the control gear, I find the 30 A estimate more than a little on the high side - assuming of course we’ve got full and accurate information.

If the 30 A is accurate, then the standard CT would of course be necessary.

@alienpepsiman, I think you need to get access to the lamps and read what it says on them. There are too many guesses and unknowns floating around here.

I think this is the light we are getting Ceiling Fans and Mobile and Wall-mounted Fans for Industry and Home

The page lists six models, do you know which one you’re getting?

10k model

don’t mix up lumens and watts. Lumens = brightness of light and not power usage
10K Lumens seems to be around 100W in your case