KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime

KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-16 00:13:52 - last edited 2021-07-16 00:20:03
Model: KP115
Hardware Version: V1
Firmware Version: 1.0.16

I have my KP115 connected to a fridge to control Power Consume and Runtime.

 

When the fridge is stopped, it keeps having 1-1.5 w on Current Power (Plug consume?), thus, KP115 thinks the fridge is still running.

 

So, it is impossible to have correct Runtime because it thinks that fridge is always running.

 

Anyway to solve this issue? 

0
0
#1
Options
10 Reply
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-16 00:36:19

@JotaMag Unless you mean you powered it off completely it sounds correct to me.  The fridge will need a small amount of power to track the temperature to decide when to switch cooling back on.  1.5W sounds pretty reasonable for a standby draw. 

AutomationManager: Secure home automation without relying on cloud servers.
0
0
#2
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-16 01:14:54 - last edited 2021-07-16 01:15:47

@MikeP ok I agree with you, but that way it is impossible to control real fridge compressor running time.

Maybe there should be in the firmware a value setting defined by user, for not consider a small consume power when plug is connected to a fridge. 

0
0
#3
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-16 12:34:01

@JotaMag I'm not sure I understand what you're trying to control or how a firmware change would help.  Perhaps if you describe your use case someone here will have a suggestion.

AutomationManager: Secure home automation without relying on cloud servers.
0
0
#4
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-16 19:35:02

@MikeP I will try to explain my question better and I apologize for my English because it is not my native language.


As I said before I have this smart plug connected to a fridge, and I want to keep track of the daily hours the fridge is cooling and its total energy consumption.


I realize that the smart plug always has a small power consumption that is needed for the fridge to control the temperature and start cooling if needed.


The problem is that this continuous small power consumption of 1-1.5 watts makes the smart plug think the fridge is working and therefore counts as running time, and the running time table says the fridge works 24 hours per day, what is not correct.


I think anyone who plugs this smart plug into a fridge wants to control how much energy it uses and how many hours the fridge's cooling compressor runs per day.


I think that by changing the Kasa application or by changing the firmware, there should be an option that when this smart plug is connected to a fridge, it shouldn't count this residual energy consumption into the running time.

 

I hope this time I managed to explain the question correctly.

Regards

0
0
#5
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-17 14:04:59

@JotaMag Ok, I understand what you're trying to do.

"smart plug into a fridge wants to control how much energy it uses" is a bit confusing - I think you mean you want to measure power usage, which it does.  A smart plug can't control how much an appliance is using other than turning it on or off (off is bad for a fridge!).

It may be a struggle to convince TP Link that the amount of power drawn should be used to decide running time or total power.  As a developer I wouldn't do it - any power draw should count as running time and is correct for most appliances.  You'll probably need an aftermarket app that can save power use over time and make any calculations needed.

 

AutomationManager: Secure home automation without relying on cloud servers.
0
0
#6
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-17 21:46:55 - last edited 2021-07-17 21:49:18

@MikeP 

Yes you are correct, I meant power usage.


I think you agree with me that if you have the smart plug KP115 connected to a fridge and app Kasa tells you that the fridge has a running time of 24 hours a day that information is not correct, and that is what app Kasa is telling me every day.

 

The minimum power usage of about 1-1.5 watts that the fridge needs to be able to control the temperature and decide when to start cooling, should not be considered for the calculation of the running time, as what is important to consider in the running time of a fridge is when the cooling compressor is working or not.

 

Thus, I think that to have a reliable running time information that is transmitted to any user from a KP115 smart plug connected to a fridge, an option should be introduced in new versions of the Kasa app or in the KP115 firmware that allows the user to set a minimum value of power drawn that does not count towards the running time, or by a question in which if the smart plug is connected to a fridge, the Kasa app only counts for the running time the time when there is high power drawn.

 

Regards

 

 

0
0
#7
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-18 12:25:05

@JotaMag To me the runtime and power are correct as is - the fridge is running, and it's drawing power even in standby.  Most users want to know the total cost of running the appliance, I wouldn't change that.

 

What you're really asking is for an additional timer that would count only when above a minimum power draw, a somewhat specialized case.

Adding this feature would be a TP Link team decision, hopefully the support team will pass it along for consideration.  You're probably looking a years of waiting if ever...

 

I imagine the power draw of the fridge when the compressor is running is considerably higher - you could measure that, and divide the total power by the average compressor power draw to calculate the running time.  I suspect the standby power isn't enough to matter - if it does, do two or 3 iterations to adjust it (subtract the standby time * standby power from the total power and recalculate run time and standby time) should get you pretty close.

 

For a graph or automated calculations you may want to look at aftermarket apps, there are a few that could do that relatively easily.  For example, when running as a server AutomationManager can log power use to a google sheet - I use formulas there for graphs and analyses, showing run time and power is pretty easy.

 

AutomationManager: Secure home automation without relying on cloud servers.
0
0
#8
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-19 12:30:23 - last edited 2021-07-19 12:31:43

@MikeP 

I agree that the power consumption should always be the total, whether it is on standby or if the compressor is running.

Regarding the running time, I no longer agree...

 

You are right when you say that the power draw of the fridge when the compressor is running is considerably higher than on standby, much higher.

 
When you say that I can measure the power drawn when the compressor is running and divide the total power by the average compressor power draw to calculate the running time, that it is the normal calculation that can be done, but not on case of a modern fridge or any recent equipment equipped with a digital inverter compressor because my fridge compressor has 7 different automatic speeds, what means 7 different power draws.

 

To stop having wrong information of a fridge having 24 hours/day of running time (because what matters on a fridge running time is when compressor is running) there should be any solution by TP-Link team, or by Kasa app internal calculation after user tells the app that the smartplug is connected to a fridge, or by a question to the user asking for a minimum power draw that should not be considered for the running time calculation.

 

Otherwise, this smartplug is useless for controlling running time on any equipment that needs to have internal temperature control to decide stop or start of any motor or compressor.

Regards

0
0
#9
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-19 15:08:17

@JotaMag I'm certain the developers intended the "running time" to be the running time of the KP115 - the time it's on and delivering power.  The *fridge* itself is still running (drawing power) even when the compressor is idle.  So the app's running time is correct and total power is correct.

 

"this smartplug is useless for controlling running time" - I think you mean "measuring", and yes I agree, measuring time in various modes is not possible with a simple device like the KP115.  You're picking "compressor idle" as the mode that you want to exclude (vs "off" and "compressor active") which makes sense for your particular requirement but it's not a general case.  Reporting times spent in different operating modes was not something that TP Link offered - it seems pretty specific to the type of appliance connected.  Maybe they'll take note here and add it to their app, but honestly I doubt it, and as I said you'll need to wait a long time.

 

With the complexity of multiple power draw levels I can't see any alternative but an aftermarket app for logging.  What you're asking is very easy to do with AutomationManager and perhaps others.

 

BTW, I'm not sure about the KP115 as I don't have one, but you might want to check/test what happens after a power outage (just unplug/replug it to test). In most cases TP Link plugs remain in the power off state meaning your fridge will not operate at all until you turn the plug back on.  Unless you're at home this also means you need the plug to connect to your wifi properly too.  Using a smart plug with a fridge/freezer can be a risk.

AutomationManager: Secure home automation without relying on cloud servers.
0
0
#10
Options
Re:KP115 - Curent Power of 1-1.5 w even when stop > impossible to have correct Runtime
2021-07-28 08:00:19

 

MikeP wrote

@JotaMag I'm certain the developers intended the "running time" to be the running time of the KP115 - the time it's on and delivering power.  The *fridge* itself is still running (drawing power) even when the compressor is idle.  So the app's running time is correct and total power is correct.

 

"this smartplug is useless for controlling running time" - I think you mean "measuring", and yes I agree, measuring time in various modes is not possible with a simple device like the KP115.  You're picking "compressor idle" as the mode that you want to exclude (vs "off" and "compressor active") which makes sense for your particular requirement but it's not a general case.  Reporting times spent in different operating modes was not something that TP Link offered - it seems pretty specific to the type of appliance connected.  Maybe they'll take note here and add it to their app, but honestly I doubt it, and as I said you'll need to wait a long time.

 

With the complexity of multiple power draw levels I can't see any alternative but an aftermarket app for logging.  What you're asking is very easy to do with AutomationManager and perhaps others.

 

BTW, I'm not sure about the KP115 as I don't have one, but you might want to check/test what happens after a power outage (just unplug/replug it to test). In most cases TP Link plugs remain in the power off state meaning your fridge will not operate at all until you turn the plug back on.  Unless you're at home this also means you need the plug to connect to your wifi properly too.  Using a smart plug with a fridge/freezer can be a risk.

@MikeP After a power outage, KP 115 stays on the last state that it had before the power outage, and it also connects again to wifi.

 

Nevertheless, I gave up with TP-Link, I installed a Shelly Plug S and I can get what I need on Shelly app.

 

It gives me a graph with hourly power draw and on the graph I can estimate when the fridge compressor starts and when it stops.

 

To fine-tune it, I put two scenarios running ("Fridge working" and Fridge stopped") in which if the power draw changes to above 5 watts it registers in the log and send to me an email and the same thing for when the power draw goes down to less than 5 watts.

 

Analyzing the logs or emails, I can see the fridge compressor running time with a minute precision.

 

0
0
#11
Options