Modern approaches to maintenance require non-intrusive testing to identify any developing problems that could, if left undetected, lead to expensive disruptive failures.
HSS offers the following as part of a non-intrusive Condition Monitoring Service.
Partial Discharge Mapping
Partial discharge occurs when solid insulation begins to break down either through age deterioration or application problems.
This deterioration can be detected and mapped to dedicated record sheets with specially designed sensitive (TEV) instrumentation while the switchgear asset is still electrically live.
This type of first pass testing enables decisions as to whether any intrusive intervention will be required.
Used in conjunction with partial discharge detection, sophisticated cameras operating in the infrared range are capable of detecting heat sources within switchgear compartments.
Printouts of the heat pattern can be downloaded and included as part of the overall reporting.
Battery Impedance Testing
Batteries are an essential and important part of the switchgear protection application. Faulty or defective cells can be detected with the battery still online. This is especially useful for simple battery systems that only have an output voltmeter, as voltmeter may be more indicative of the charger output than the battery status.
As part of the application of Condition Monitoring the general condition of the substation is included as part of any final report. Typical of the data recorded is humidity and temperature at the time and date of the non-intrusive testing.
Other important recorded factors will be a presence of any standing water in cable trenches, defective lighting, defective locks and any general building damage.
This would all be supported by photographic evidence.
Standards and Application
All tests offered by HSS as part of a Condition Monitoring package are to British Standards.
They can be applied as a one-off occurrence or can form part of an overall ongoing programme of activities to all types and makes of switchgear, irrespective of asset age.
Increasingly the demand for cost reduction has to be balanced with the need to complete essential maintenance work. Based on proven techniques and data, the elapsed time span between maintenance cycles has increased for some users of HV and MV switchgear.
Maintenance is by definition an intrusive activity.
The cost of the actual maintenance has to be coupled with the cost of the downtime of switchgear to get a true picture of what maintenance costs mean to some users. However, failure to complete maintenance can lead to expensive disruptive failures.
Hawker Siddeley Switchgear (HSS) offer a non-intrusive condition monitoring service that provides an insight into the status of the switchgear without equipment being removed from service.
Detailed reports then give the switchgear user the opportunity to make an assessment based on the findings and either give the switchgear a clean bill of health or plan for an unforced intrusive intervention.