Howard Medium Power Substation - Manual (Page 9)

Medium Power Substation Transformers
Document 2.4.06, Revision 4
June 2013
9
Annual Inspection
The annual inspection should include the following
checks in addition to the quarterly inspection checks
listed above.
1. Check paint finish and repair any damage.
2. Test insulating fluid for dielectric strength and
moisture content.
3. Test insulation with a Megger test set. (Omit if
bushings have not been installed.)
4. Check insulation power factor with a Doble or
similar test set. (Omit if bushings have not been
installed.)
5. Transformer fluid containers or totes should be
visually inspected for damage and any indication
of water intrusion or other contamination.