Power Quality - Applying data to fix poor power (success)

How was your issue detected?: Flickering lights

Did you noticed any other signs of this issue around your home?: High draw motors (well pump) caused flickers also.

I thought I would share a success story that Sense power quality monitoring enabled.
We have had flickering lights for a long time and it only got worse as more lights were converted to LED. Less power used but more sensitivity to voltage and quicker response time of LED vs heated wire.
When Sense enabled the power quality monitoring (and I got around to trying to deal with the issue) it showed this:

A few days later it was still not the best.

I started the process of contacting the power company (Xcel Energy). When their tech showed up several weeks later in the morning he had load testing equipment to try and diagnose the line issues. Between short highest power loading and long loading he was not seeing issues. I was watching so I could pepper him with questions and he answered them all.
I then pulled out my phone and showed him the voltage graph (and list of dips) from the last 24 hours. I could see in his actions that this changed his mind from if there is a problem to what is the problem. (Love data).
He then went to look at the transformer. My neighbor and I share 1 transformer. We both have 200 Amp services. The transformer was rated at 10KV. The tech decided that the transformer was undersized and put in a work order to have it replaced.
A few weeks later Xcel was removing the 10KV and putting a 50KV transformer on the poll.

Can you tell in the graph when the transformer was changed?


So thank you Sense for proving the data to truly fix the issue.
Dean Hoyt

13 Likes

This is great @greycloudman, thanks for sharing - pictures are always very appreciated here.
What state are you located in?

Mn, close to St. Paul.

Have Fun
Dean