Wattage versus kWh readings for UPS

[abrunero]

Hi. I was asked what is the energy consumption showing through the UPS in a site. This is our own Schneider Electric site Le Vaudreuil in France. I look at each of the 5 UPS monitored at their sensors. From the average of 30 days kWh I read total 17,320 kWh. For the same reading (average over last 30 days) of watts, the total I get is 2,694 Watts. The Watts and kWh readings from the same UPS don't seem to line up. Am I missing something? Thank you!

[Cory_McDonald · Accepted solution]

Hello @abrunero,

kWh is an accumulative sensor that continues to increase over time until it is reset.  For this reason, you can not average the kWh sensors and get a true overage usage for the last 30 days, but you have to compare the highest and lowest values to get a delta of increase over the duration of the month.

Watts measurement is usually not an accumulative sensor over time.  It is a look at the exact moment in time of what is being consumed. An average of this would show the average of watts used at any point in time over the 30 days.

To compare these 2 values you would need to take the delta of kWh (Highest value - lowest value or 30 days ago - current moment) and the average of the watts over the past 30 days and compare them by converting either kWh to watts or watts to kWh.

Regards,

Cory

[abrunero]

Thanks Cory! Makes sense. I took the average wattage reading from the UPS and calculated the average kWh from there over a period of time. Appreciate the quick response!