When PG&E decided to add over 200 new FLIR i7 thermal imagers recently, Substation Maintenance and Construction Supervisor Ray Friend explained the reason was simply a matter of common sense. "Safety is always the first thing we want to think about. And a big thing I get from talking to the people now using an IR camera is the confidence it gives them in the equipment they're going to be working on. They want to know if something is operating (within safety parameters) the way we expect it to, whether it's oil-filled equipment or an air switch under load."

Friend says crews now routinely do a quick scan to look for unusual hotspots on a variety of components that may need maintenance. "If you're required to stand at the end of a 16-foot disconnect stick, ready to rip a switch open, you want to be able to trust that the switch is properly adjusted and going to do what it's supposed to... that's what the camera gives us." In other words, it helps them see heat anomalies that signal potential danger.

More IR Scans More Often

While PG&E continues to use high performance FLIR cameras for their more intensive and detailed IR inspections, Friend said the low-cost i7s make it possible for his team to use thermal imaging more frequently on their rounds and on a moment's notice. "It's simple to operate...there's no rocket science involved...you can interpret things easily on the screen...all you need to have are a [few] instructions as to what to look for. And it's portable and seems to be very rugged. We have them in trucks bouncing around and have had no issues."

Since electrical equipment tends to get hot before it fails, Friend says it's good to have a FLIR handy. "Normally what they're finding is loose connections, switches out of adjustment, regulators and breakers that are running too hot. They're also finding oil-filled bushings and other equipment with abnormal temperature differences that indicate a lack of cooling."

ROI: Repair vs. Replace

For example, an electrician doing a routine substation inspection in the San Joaquin Valley not long ago was passing within five feet of an energized transformer bank and quickly became alarmed. "Normally, you would expect it to give off some heat but this thing he could instantly feel on his face," Friend recalled. "So he immediately grabbed his i7 from the truck and took a picture and verified within seconds that there was an issue...it was white hot. He called his supervisor from his cell phone and was able to show what the thermal camera saw. The supervisor immediately took that thing out of service." According to Friend, once offline, they found there was absolutely no oil flow in the transformer. "By catching it in time, we spent only about $300,000 to repair that transformer bank. That's a major savings compared to the roughly $3 million to replace it, which we would have had to do if it had completely failed and been destroyed."

Friend pointed out that the weeklong repair work requiring a crew of six was a quick turnaround. In fact, it's about one-sixth of what it would have taken to wait for a replacement, if they could have found one in that time-frame since sometimes delivery on such equipment can span months. Fortunately, in this particular substation location, detecting the problem early and distribution workarounds helped the company and customers avoid the impact of a serious outage.

An Ounce of Prevention...

Friend says that across the board thermal cameras have allowed PG&E to find issues early that would have eventually shown themselves but perhaps under more serious circumstances. "We're catching them a lot sooner...in time to deal with it properly and safely...long before it fails." That gives PG&E much better control over a situation, allowing them to more effectively target and plan repairs that help prevent expensive emergencies and shutdowns. With the ability to uncover hidden problems well in advance when they can still be repaired instead of being replaced, Friend feels affordable point-and-shoot IR cameras like the FLIR i7 pay for themselves in no time. "If you can spend a nickel today rather than ten dollars tomorrow, why wouldn't you want to spend it now? It just makes sense operationally...[and] safety-wise."

Covering More Ground

Efficiency is also a factor. Inspections go much faster with thermal imagers than they do with IR thermometer guns, for example. That's because temperature guns require scans to be performed close to the target for accuracy, only provide one reading at a time, and don't produce a picture, making surveys of the many electrical components in a substation a painstaking process. Compare that to the instantaneous images and thousands of detailed measurements you can capture from a safer distance with a thermal camera, and the potential for increased productivity becomes obvious.

The Bottom Line

As Ray Friend put it, "If you look at PG&E's vision, where we're providing reliable, safe energy to the public, any tool like this that allows us to do that, to [help] prevent outages and catastrophic failures...it's got to pay a lot of benefits both to the company and to the public."