[keikeoki]

The power factor of a typical hvac system is .8 to .9.  So 6.79 amps converted from a true power reading is correct. to turn that into actual; amps you need a power factor meter to give you the pc to adjust to your measurements.  It sounds to me like your fluke and Emporia are in agreement, you just don’t know the power factor to use to compare the two numbers.

The fact is Emporia is guessing the amps based on a power factor of 1.  Your actual power factor will be lower because the inductive loads do not consume power for the full  sine wave cycle.  Your fluke is showing the actual measured amps, which cannot be used by itself to derive accurate watts.  V * A =VA not watts.  If your furnace was electrric only, that .8 power factor would be a lot closer to 1 because the main load would be resistive.  The resistive heating elements have a pf of 1, motors are closer to .8, and the computer circuit boards are closer to .65.  Doing a direct conversion from VA to watts is not possible without a power factor measurement, and your fluke doesn’t do that…  Even my new DVM’s won’t calculate pf, it takes a power/energy meter to do that.  Nothing wrong with your fluke, the problem is it is the wrong kind of meter for this.  Funny thing, as often as engineers with vom’s are doing math in watts, you would think the VOM’s would include either direct readings in watts, or a power factor measurement so you could do it yourself.

I used to manage data centers, and it is a larger problem with computers as they are in the .65 range so going off of VA and you are going to be really inaccurate.  You can just plug in a guess as to the power factor, and even though it is a guess it is more accurate than not making any pc adjustment.

Do this, clamp onto the resistive element, VA*1=watts.  Clamp onto each motor, VA*.8=watts.  Clamp onto the transformer powering the electronics, VA*.65=watts.  Add those values together and see if emporia agrees.  Ignore Emporia’s amps, it isn’t a real measurement, only look at watts.

[keikeoki]

Greetings!

I’m an engineer going way back with automation and Internet integration.  My first Internet based automated control aps were all created around 1990, as I took some of the first steps at applying automation to the ISP I was starting.  I later became the hardware engineer for a smartphone project called the Intelliphone around 1990, and I am to blame for why our smartphones are connected to the Internet.

I’ve been an emporia customer since the Texas snowmageddon, when I discovered I was billed for power usage on a day I had no power for the whole day.  But until today, I never found my way here.

I’m here with you today to find out why emporia doesn’t show up on the ifttt integration site.  When I first got my emporia equipment I remember reading that ifttt was being developed, but I got busy…  Here I am today, having moved my emporia gear to new mexico, and I installed  remote controls all over my house…  I just assumed that I would be able to flip my emporia switches on and off by now.  I’m back in texas today, attempting to set up some ifttt automations, and I am surprised that my emporia switches were the wrong pick…  And I bought so many.  So while I CAN write some automations, I can’t write the ones I need the most.

The good news is I can still do what I need to do manually, it’s just not as good.  It’s my fault for just assuming that by the time I needed ifttt it would be here…  I’ve been an engineer for a long time, I should know better.  But that’s not going to stop me from pestering y’all.  Sign me up as a beta tester for ifttt…

I love my emporia products, I use them as the tools that they are.  They are a fine fit for all of the other measurement tools I have, and quite convenient compared to any of the clamp-on ammeters, current tap oscilloscope probes, and other tooling I have.  And that I can use those tools from a thousand miles away is a great thing.  There is only one thing missing….IFTTT!!

Keikeoki

• This reply was modified 1 year, 9 months ago by keikeoki.

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