Srpski English Русский

Substation Maintenance


Annual revision and service of a substation is necessary, beside the legal obligation, in order to check preventively and measure the functionality of all parts of equipment in the substation.
In the case of remaining without power, you can always, at any time, rely on us. Our professional teams are at your disposal to diagnose and repair the defect using the latest technology equipmentin order to provide you with uninterrupted power supply.

Optionally, your defective transformer can be replaced with ours during the period of repair service.

Beside this, to prevent this kind of situations, we offer a preventive annual maintenance of substations through which we, by the means of reports, indicate observed defects and suggest solutions.
Maintenance consists of the following:

1. Measurement of the insulation resistance of the transformer windings, between the windings HV-LV, between winding and earth HV-G and LV-G.

2. Protection check of the operation of a transformer (Buchholz relay and contact thermometer) as well as the activation of transformer’s protection by the action of Buchholz relay on the shutdown of main HV disconnectors of power of the transformer.

3. Examination of the equipment for grounding and measurement of the ground resistance.

4. Thermo-vision recording of electric installations with the preview of potentially defective places, contacts, etc.

5. Revision and cleaning of HV and LV cable endings and insulators with tightening of coupling points. Thorough cleaning of the dust and cobweb from substations.

6. Control of the transformer tanks gaskets, check of all gaskets with the cleaning of upper plates, insulators and connectors of the transformer.

7. Oil draining from lower drain valves, sampling of transformer oil for the examination, measurement of dielectric permittivity in our laboratory. Pouring of drained transformer oil into conservators of the transformer, and, optionally, adding of new transformer oil in adequate quantity.

8. Detection of PCB oil presence (polychlorinated biphenyl) in transformer oil by the use of theindicative method and a CLOR-N-OIL set.

9. Replacement of silica-gel in the air dryer of a transformer.

10. Examination of protection on MV and LV plants.

11. Check of the operation and cleaning of LV switches along with the check of levering spring drive, check of the operation of the mechanism for activation-deactivation of the switch with the tightening of the connectors.

12. Writing and delivery of Examination checklists, technical report and expert’s finding on executed service of your substations.