• Saves money by eliminating wasteful, time-based maintenance
• Minimises disruption to the network in a cost-effective way by obtaining samples while part of the unit remains live
• Measures oil condition accurately, indicating if maintenance is required
• Safely extends periods between maintenance interventions
• Warns of switchgear degradation before it leads to failure
• Increases asset reliability while also reducing costs

Techniques used for Live Tank Oil Sampling

By using oil quality and filtration techniques, it is possible to understand the internal condition of the units and accurately determine whether invasive maintenance is required.

Oil Quality

The oil quality technique measures moisture, acidity, and electrical breakdown strength. These parameters are primarily intended to give information on the condition of the oil, although indirectly they also provide some information on the condition of the switchgear unit.

Filtration & Solid Contamination Assessment

The oil is filtered through a filter paper using a vacuum pump to draw the oil through. The contamination and residue is collected on the filter paper which is then dried and analysed under the optical/scanning electron (SEM) microscopes to identify the particulate. Typical particulate include fibres, debris, insects, metallic materials, paint flakes and insulation materials. This test allows a deep understanding of the degradation of the oil and internal components.

Easy to interpret results

The results are provided in an easy-to-interpret ‘traffic light’ summary. After the oil analysis is completed at the EA Technology Oil Diagnostics Facility, the asset is given one of four ratings: Pass, Retest, Maintain, Action.

PASS:
Satisfactory oil condition, which enables an extended maintenance interval to be adopted and the unit should be re-sampled in five years.

RETEST:
Evidence of some oil degradation, the unit should be retested in 30-36 months (half PF interval for oil degradation).

MAINTAIN:
Indicates very poor oil quality, unit should be maintained within 6 months.

ACTION:
Extremely poor oil quality indicating the unit is prone to a catastrophic failure in the short term and the client will be advised accordingly.

With typically over 90% of assets gaining a pass grade, it is clear that Live Tank Oil Sampling can result in a significant reduction in unnecessary inspections and maintenance. This can result in substantial savings on maintenance budgets.