Multiplier not applied in Amps

[esauser]

When viewing in Amps the multiplier is not applied.

[djwakelee]

Believe this is correct operation at this time, and a fix to an existing bug where Amps were being multiplied.  With the latest app it appears that the multiplier currently applies to volts on the circuit.  There isn’t a separate multiplier field for volts and amps, so they picked one (useful for using 1 clamp on 240V circuits).  In that case, as volts are doubled, power is also doubled appropriately.  This provides a valid workaround until proper app support for single clamp 240V is rolled out, as well as dual clamp combined summing.

Multipliers for amps would be useful to calibrate the CT’s, or if using the Vue with alternate CT’s with different ratio.  Probably not a supported scenario.

Believe older app versions behaved differently, where amps/volts/watts were all multiplied.

[esauser]

What you described is what I’m doing. I have 2 240v that I’m monitoring 1 leg on, with a multiplier of 2. When looking at any other unit of measure other than amps it is properly doubled. Amps, however, are unchanged.

 

It seems a bit odd that would be intentional since the numbers no longer line up with the totals from the mains.

[djwakelee]

Amps shouldn’t be doubled in that case for that circuit (with the single clamp for 240V on the one leg).  The current flowing through the 240V circuit is the same whether you have 1 clamps, 2 clamps, or x clamps – on any of the legs.  What is different about using 1 clamp on 1 leg is that the voltage is 240V, versus 120V for any of the normal split phase circuits.

What they really need to do is allow you to indicate which ports are being used for 240V circuit measurement, and the type (single or dual leg clamp).  If setup for single leg, amps is amps, and power is obtained by multiplying the measured amps by the phase 1 voltage + phase 2 voltage.  If using two clamps (such as an unbalanced subpanel feed), allow the visual list to sum up the total power.  Better support for 240V circuits has been promised in a future app update.

So I think it is correct to not apply the multiplier to the amps (current).  Do they have an issue with the amps total and balance, that is likely.

[bedpan]

Just discovered this bug myself. Appears to still be an issue! They need to let you specify it as a 240V Circuit. Come on guys this was reported 6 months ago I should not be re-discovering it now it should be fixed!

Also it seems that Notifications do not work on multipliers. This is what I came to report. I will create a separate thread.

[derson]

Same problem here.  I feel the explanation above is inaccurate and I cannot believe has not been fixed for 120v 2-phase boxes.  An example: a double oven that has a single oven running pulls about 15 amps on each of the two separate 120v phases (2 x 15 x 120).  Measuring a single leg with a 2.0 multiplier correctly shows 3600 watts in the app for power of the device, switching to amps only shows 15 amps of power draw (ignoring the multiplier).

If I had both circuits monitored and could sum their readings in the app, the app would show 30 amps of power draw across the two 120v legs. I expect the multiplier to behave the same way!

So calculating the total amps used in the electrical box is off.  I think that is dangerous!  With a double oven, an electric cooktop, AC, a clothes dryer, an electric car, all pulling two legs (240v), a 200 amp panel could show that only 60 amps are in use with all the 240v devices turned on when measuring only individual circuits… when 120 amps would actually be in use!

Part of me understands why they are using the multiplier on the voltage because it may look weird pulling 60 amps across the dual-40 amp breaker, but that would be more accurate when we intentionally set a multiplier!   Since it does not make sense to show voltage per circuit, applying the multiplier to amps makes more sense to me.

At a minimum, the app should clearly show that a 240 volt circuit (or multiplier x volts) is being displayed when switching to amps… but leaving that out incorrectly shows the amps being used.

[Emporia Support]

Hello @derson A 240V appliance connects to two hot legs and a ground (no neutral), so if it pulls 30A, that 30A has to be going in one hot leg and out the other hot leg — there’s nowhere else for it to go (no neutral).  In other words, it draws 30A — the legs do not “add together”.

 

 

[derson]

Thanks @emporiainfo.  It would be great to show the multiplier/voltage on the amp graph when different from the primary voltage. I was wrong about the amperage in my post above.

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