SolarRat
Solar Addict
That's exactly what my cable does, same idea.
So here is My DIY "Kill-A-Watt" meter
- Thread starter SCClockDr
- Start date
That's exactly what my cable does, same idea.
erik.calco
Solar Badger
I got one of these for $12 for AC. 
Wired an extension cord through it so I can just plug things in. Used separate plug for powering it to keep it separate, but there is a way to do it with one plug w/o counting the units current. Wish I could find a face plate for it so I could mount it in a box, ideally a 2 gang with outlets.
It remembers accumulation even when you unplug it. You can reset it by holding down the button that turns light on/off.
My transfer box has two hall sensors for the gen lives with analog meters to measure load.
Wired an extension cord through it so I can just plug things in. Used separate plug for powering it to keep it separate, but there is a way to do it with one plug w/o counting the units current. Wish I could find a face plate for it so I could mount it in a box, ideally a 2 gang with outlets.It remembers accumulation even when you unplug it. You can reset it by holding down the button that turns light on/off.
My transfer box has two hall sensors for the gen lives with analog meters to measure load.
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jasonhc73
Cat herder, and dog toy tosser.
While this pi monitor is super neat, it's price makes no sense. Emporia VUE with 8 CT is $99.If you are looking for more of an energy monitoring system, check out Open Energy Monitor.
Home | OpenEnergyMonitor
openenergymonitor.org
I built something like this a few years ago for my well control system. My system used some of the basics from the OEMon project but it does a lot more than just energy monitoring. It provides overload and underload (dry well) protection for the pump and manages the pumping cycles to avoid excessive draw down.
Mars
Venezuela Solar
New Member
- Joined
- Dec 6, 2019
- Messages
- 146
I made my vary similar (with a wooden frame) the best part is that the kill-a-watt only supports more or less 1800w, with this meters there is almost no equipment you cant measure and if you use 2 meters and 2 outlets you could measure 240v equipment and 120v equipment, one coil measures two wires (one from the 120v outlet and one 1 from the 240v outlet) the other coil only one wire from the 240v outlet and with a selector switch would turn on one or both meters, that would be like selecting 120v or 240v, for the power input you would need a detachable wire so you would connect the right terminal for 120v or 240v, maybe with some anderson plugs, just an idea that cross my mind
SCClockDr
Solar Enthusiast
I may install a mini audio jack and attach a split coil to an audio plug. I'd need to re-wire the original internal coil to go through the audio jack sup plugging in the external jack would switch coils.
That way I could sample hardwired circuits as well.
That way I could sample hardwired circuits as well.
Hedges
I See Electromagnetic Fields!
- Joined
- Mar 28, 2020
- Messages
- 21,015
Always offering a more expensive way to accomplish exactly the same task, here's my setup:
100A current transformer, $3500, 50 MHz high voltage differential probe, $24,000 1 GHz deep memory oscilloscope.
Those of course are msrp, I buy obsolete, or new old-stock when available.
For the ultimate in Prepper setup, this ITAR controlled instrument can one-shot digitize the "event", so you can run FFT and see what spectrum it produced when knocking out the entire North American power grid.
For more mundane uses, I capture startup surge of motors, view phase-shift of reactive loads, calculate power factor.
I've now got current transformers installed on both legs of my battery inverter, going to BNC. I'll be able to capture waveforms for any 120 or 240V appliance in the house.
www.nscainc.com
100A current transformer, $3500, 50 MHz high voltage differential probe, $24,000 1 GHz deep memory oscilloscope.
Those of course are msrp, I buy obsolete, or new old-stock when available.
For the ultimate in Prepper setup, this ITAR controlled instrument can one-shot digitize the "event", so you can run FFT and see what spectrum it produced when knocking out the entire North American power grid.
For more mundane uses, I capture startup surge of motors, view phase-shift of reactive loads, calculate power factor.
I've now got current transformers installed on both legs of my battery inverter, going to BNC. I'll be able to capture waveforms for any 120 or 240V appliance in the house.
Tektronix TDS784D 4 Channel, 1 GHz, Digital Phosphor Oscilloscope – NSCA Technologies & Tra-Cal Lab
Tektronix TDS784D 4 Channel, 1 GHz, Digital Phosphor Oscilloscope
www.nscainc.com
carlos1w
Lego Man
- Joined
- Jul 9, 2020
- Messages
- 113
Why would he need µs time resolution?
Hedges
I See Electromagnetic Fields!
- Joined
- Mar 28, 2020
- Messages
- 21,015
Microsecond? At 4 GS/s my setup can give nanosecond resolution; 8 meg memory depth that would be limited to 2 ms capture, 1/8 of a line cycle.
But not with the current transformer, and not the HV probe, due to their bandwidth. Only with suitable voltage probes.
Why? Because we can.
That's just my lower end home system.
Recent job, I was measuring 5 kV 100 ps pulses into 50 ohms.
All it takes is the right equipment (and deep enough pockets)
my boss noted that scopes run about $10k/GHz, which would make this one a bargain.
But not with the current transformer, and not the HV probe, due to their bandwidth. Only with suitable voltage probes.
Why? Because we can.
That's just my lower end home system.
Recent job, I was measuring 5 kV 100 ps pulses into 50 ohms.
All it takes is the right equipment (and deep enough pockets)
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my boss noted that scopes run about $10k/GHz, which would make this one a bargain.
carlos1w
Lego Man
- Joined
- Jul 9, 2020
- Messages
- 113
Microsecond? At 4 GS/s my setup can give nanosecond resolution; 8 meg memory depth that would be limited to 2 ms capture, 1/8 of a line cycle.
But not with the current transformer, and not the HV probe, due to their bandwidth. Only with suitable voltage probes.
Why? Because we can.
That's just my lower end home system.
Recent job, I was measuring 5 kV 100 ps pulses into 50 ohms.
All it takes is the right equipment (and deep enough pockets)
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Find many great new & used options and get the best deals for Keysight DSAZ634A 63ghz 160gs Scope Super Loaded Cal Plan to Nov 2024 at the best online prices at eBay! Free shipping for many products!www.ebay.com
my boss noted that scopes run about $10k/GHz, which would make this one a bargain.
You still did not answer what purpose (other than "because I can") would this serve. The answer is none. BTW: in 1 ns, light travels 0.3 m, electricity in a wire at least 10-100 times less. So all local measurements are not very representative of what is happening just a few cm away.
Hedges
I See Electromagnetic Fields!
- Joined
- Mar 28, 2020
- Messages
- 21,015
milliseconds is sufficient for surge current.
Electricity in a wire (insulation relative dielectric constant 4) travels 1/2 the speed of EM waves in air.
I use 12"/ns in air, 6"/ns in cables or PCB to do math in my head.
Local measurements will show what's happening feet, even miles away. Just have to be patient waiting for the signal to arrive.
The higher frequency signals will also be more attenuated if distant, which can be good or bad depending on what you want.
What microsecond is good for is seeing high frequency power supply switching and spikes.
Ghz is good to see arcing (from kHz into MHz), as well as RF pickup. Those can confuse arc-fault circuits.
That's beyond what someone needs in terms of kill-a-watt to size their system. It would be for R&D or problem solving.
Yeah, I'm something of a technology geek. And a Luddite.
Electricity in a wire (insulation relative dielectric constant 4) travels 1/2 the speed of EM waves in air.
I use 12"/ns in air, 6"/ns in cables or PCB to do math in my head.
Local measurements will show what's happening feet, even miles away. Just have to be patient waiting for the signal to arrive.
The higher frequency signals will also be more attenuated if distant, which can be good or bad depending on what you want.
What microsecond is good for is seeing high frequency power supply switching and spikes.
Ghz is good to see arcing (from kHz into MHz), as well as RF pickup. Those can confuse arc-fault circuits.
That's beyond what someone needs in terms of kill-a-watt to size their system. It would be for R&D or problem solving.
Yeah, I'm something of a technology geek. And a Luddite.
Hey all, I'm sorry to jump an old thread but this might be close to what I and more than a few others are looking for. I have a large freeze dryer that has a Nema 5-20 plug and draws a peak of 16 amps on a 20 amp breaker.
Have exhaustively searched for a 20 amp rated kill-a-watt meter that measures current usage and elapsed usage (amps, volts, watts and most importantly, KWH).
Does this set up measure these both current and elapsed?
Could anyone help me with a build or instructions to build? I am probably not qualified to do this but my electrician might be able to.
Thanks for any help you can provide...there are a lot of us begging for a meter that will work ...
Have exhaustively searched for a 20 amp rated kill-a-watt meter that measures current usage and elapsed usage (amps, volts, watts and most importantly, KWH).
Does this set up measure these both current and elapsed?
Could anyone help me with a build or instructions to build? I am probably not qualified to do this but my electrician might be able to.
Thanks for any help you can provide...there are a lot of us begging for a meter that will work ...
Lt.Dan
Solar Wizard
Check out https://www.themeterbox.com
They do exactly what the OP made. It's original intent is to track power usage of Crypto miners, but they are just a glorified kill a watt with current/watt usage and elapsed usage.
Thank you sir! This might work perfectly! Checking into it???