Negative Watts

Read page 38 of this manual.

Regards

Allow me to answer your question with a series of question and answers that should actually help you to figure out what is happening.

• Can an ambiguous energy spike from an unknown source into an unspecified network cause damage? Yes, it can. However, since you are asking us what is happening instead of busily replacing some dead equipment I suspect the damage is not very severe.
• Can the damage be difficult to find? Yes, it can.
• Can this energy do absolutely no harm to the network? Yes, it can. It all depends on where and how this energy gets deposited.
• Can this energy spike actually be a ghost image from some defective or improperly utilized instrumentation? Yes, it can easily be a ghost.
• Can this problem be clearly identified and solved without schematics and further testing? No. Troubleshooting this type of a problem cannot be done without hands on testing, schematics in hand and a firm grasp of circuit theory.

I don't mean to be glib here. I hope that my questions and answers spur you into some well organized testing that will reveal your actual situation, if this situation requires remediation and how to accomplish this remedy if needed.

I'm a complete novice here when it comes to answering a question like yours. But I decided to make a reply because you didn't seem to get much help.

It would seem to me that a piece of equipment would be causing the spike, although you mention a 15 minute window. I don't know if you mean the event has a 15 minute duration... But the reason I think you might be seeing it is because of the UPS kind of back-charging.

The only thing I could suggest is to monitor the meter as different tools were switched on and off.

Thanks for the replys. I just found this Friday when I pulled up a report for another reason so I am just starting an investigation. If anyone has some pointers or has found something causing this problem, let me know.

I will try to post on my findings.

Jeff

You don't say what your Power Factor is recording at at the time of the event. You could have a grounded leg causing the event in a seldom used piece of equipment or someone doing something they shouldn't with something with significant energy usage.