Transformer Oil Sampling and DGA Submittal Inspection

It covers the full path from field sampling to lab interpretation: transformer identification, sampling conditions, sample integrity, chain of custody, laboratory receiving confirmation, and DGA review. The checklist is designed to catch problems that make a gas analysis unreliable, such as air ingress, poor labeling, or missing transfer records. It also captures the follow-up action tied to the reported gas pattern.

Use it whenever you collect insulating oil for dissolved gas analysis, whether for routine condition monitoring, post-event investigation, or a suspected fault. It is especially useful before sending a sample to the lab, because many failures happen before the analysis ever starts. If the sample was taken under uncontrolled conditions or the custody trail is incomplete, this template helps document the deficiency.

A trained and authorized technician, electrician, reliability specialist, or utility field inspector should complete it, depending on your site procedures. The person taking the sample should be the same person, or part of the same workflow, who can verify the chain of custody and submittal details. The template is also useful for supervisors reviewing contractor work.

Use it every time a sample is collected and submitted for DGA, not just on scheduled maintenance rounds. For assets on a condition-monitoring program, it can also be used to audit a sampling event after the fact. If your program includes repeat sampling after an alarm or abnormal gas trend, this template helps keep each event consistent.

Yes, the template is built to capture the documentation needed to support IEEE C57.104-style interpretation and Duval triangle assessment. It does not replace the lab or an engineer’s judgment, but it ensures the sample context, reported gases, and follow-up action are recorded in a way that supports those methods. That makes the result easier to defend during maintenance review or incident investigation.

Common issues include sampling from a dirty or inaccessible port, not flushing the line before collection, allowing air to enter the sample, using the wrong container, and incomplete sample labels. It also catches chain-of-custody gaps, missing lab receiving confirmation, and DGA reports that omit the interpretation or recommended action. Those deficiencies can make a valid fault trend look normal or make a normal sample look suspicious.

Yes. You can add transformer asset tags, station names, lab account numbers, shipping instructions, alarm thresholds, or site-specific acceptance criteria. Many teams also add fields for prior DGA trend comparison, moisture, dielectric strength, or furan testing if those are part of the same maintenance program.

An ad-hoc checklist often stops at 'sample taken' and misses the details that determine whether the result is trustworthy. This template forces a structured review of safety, sample integrity, custody transfer, and interpretation, so the final report is usable for maintenance decisions. It also creates a repeatable record that is easier to audit across multiple transformers and technicians.

Yes. The fields map well to CMMS records, asset management systems, and laboratory submission portals because the template follows the same sequence used in the field. You can attach photos, upload custody forms, and store the lab report alongside the inspection record. That makes it easier to trend results over time and retrieve evidence during audits.