question

bazil avatar image
bazil asked

Can anyone explain the watts anomaly in the attached image: UPS plugged into inverter?

Can anyone please explain what might be causing the following:

I have a 12 V to 240 V pure sine wave inverter (1000 W); for purposes of experimenting, I have placed a measuring device between the load and the inverter's AC output

If I plug a 60 W incandescent lightbulb into the socket, 60 W is displayed on both the inverter's display and the measuring device.

However, when I plug-in a (small) fully charged UPS unit into the same socket, a load of 48 W is displayed on the inverter and 18 W on the measuring device.

If I plug the same UPS into the mains, the measuring device equally displays 18 W.

Any ideas why there is a 30 W difference?

Best regards
Stephen


img-9214.jpg

inverter current drawups
img-9214.jpg (1.2 MiB)
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
mvas avatar image
mvas answered ·

The inverter computes the watts consumed by a highly inductive load, differently?

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

kevgermany avatar image
kevgermany answered ·

Google power factor. But this seems pretty bad.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Related Resources

Additional resources still need to be added for this topic