Online DGA: Manufacturers

[111R]

Now that the online DGA monitors are becoming more common, there are a few manufacturers to choose from when making a selection.

Does anyone have experience with the GE Kelman Transfix, Qualitrol Serveron TM8, or others that will provide 8 critical fault gas monitoring capabilities? What did you find to be the pros and cons of each? How did you integrate it into your SCADA network? Do you have full remote access or do you make a site visit to access data?

Thanks for any input.

 

[bacon4life]

Be aware that electronics seem to have a 5-10 year lifetime, far shorter than the expected lifetime of a transformer. I choose to install single gas monitors on 3 of our transformers because they seemed to have drastically lower ongoing maintenance costs. Unfortunately, the LCD screen died within about a year on all the units.

Making use of the data has been much more challenging than I expected due to increased cyber security restrictions at my utility. We currently bring back a 4-20mA signal plus the alarm contacts. Remote access seems even less likely with the new version CIP standards. Even though the DGA monitors were factory installed by the transformer manufacturer, I think we spent nearly as much in labor getting the communication up and running as the list price for the monitor.

That being said, we did add a requirement to our specification that all new substation transformers have valves installed to accommodate future online DGA. In the case of a suspect transformer, online DGA seems like a great idea.

 

[LSpark]

It's not my area of specialism but we switched from using Hydran to Calisto for our (European) GSUs due to on going maintenance costs. I was on the operational side when I was site based so don't know how easy or hard it was to intergrate into our SCADA network. We used to get a single value from the Hydrans, it wasn't a substitute for having routine DGA samples taken and analyzed and was on the GSUs only. Any unexpected upturn in the value from the Hydran would trigger an additional oil sample being sent for testing.

 

[inpran]

I have come across Calisto and A-eberle make online DGA monitoring devices in different projects. We had both integrated to SCADA (relays were specifically ordered with the 61850 protocol) and did not have much issue during integration of both of them. Data collection was fully remote.