Howard HI-102 Overhead Transformer User Manual
Page 4

Document 2.4.95, Revision 0
May. 2013
4
Fluid-Filled Overhead Distribution Transformers
Surge Arrester .............................................................................................................................................................16
External Surge Arrester ...............................................................................................................................................16
Internal Surge Arrester................................................................................................................................................16
Low-Voltage Circuit Breaker........................................................................................................................................17
Magnex Interrupter .....................................................................................................................................................17
Other Switching and Fusing Devices ..........................................................................................................................18
SECTION 6: OPERATION OF BUSHINGS, GAUGES AND ACCESSORY DEVICES ........................................................19
Hot-Stick Operable Devices ........................................................................................................................................19
Pressure-Vacuum Gauge ............................................................................................................................................19
Fluid Level Gauge and Sight Plug ..............................................................................................................................19
Fluid Temperature Gauge ..........................................................................................................................................19
Drain Valve and Sampling Device ..............................................................................................................................20
Automatic Pressure Relief Valve ...............................................................................................................................20
Internal Fault Detector ...............................................................................................................................................20
Bushings and Terminals ............................................................................................................................................20
High-Voltage Bushings ...............................................................................................................................................21
Low-Voltage Bushings ................................................................................................................................................21
Other Accessory Devices ............................................................................................................................................21
SECTION 7: MAINTENANCE AND REPAIR ......................................................................................................................22
Periodic Inspection......................................................................................................................................................22
Inspection Checklist ....................................................................................................................................................22
Electrical Tests ............................................................................................................................................................23
Exterior Paint Finish ....................................................................................................................................................23
Fluid Leaks ..................................................................................................................................................................24
Audible Sound Level....................................................................................................................................................24
Low-Voltage Circuit Breaker........................................................................................................................................24
Magnex Interrupter .....................................................................................................................................................25
Other Accessory Devices ............................................................................................................................................25
Insulating Fluid ...........................................................................................................................................................25
Sampling the Fluid .....................................................................................................................................................25
Filtering the Fluid ........................................................................................................................................................25
Removing or Lowering the Fluid .................................................................................................................................25
Filling with Fluid ..........................................................................................................................................................25
Opening the Transformer Tank ..................................................................................................................................26
Torque Guidelines .......................................................................................................................................................26
Additional Maintenance Instructions ........................................................................................................................28
Repair Parts ................................................................................................................................................................28
Warranty Claims .........................................................................................................................................................28
Disposal ......................................................................................................................................................................28
Tables
Table 1: Torque Guidelines for External Cabinet Fasteners .....................................................................................27
Table 2: Torque Guidelines for External Bushing Mounting Hardware ....................................................................27
Table 3: Torque Guidelines for External Bushing Terminal Connections .................................................................27
Table 4: Torque Guidelines for Accessories ...............................................................................................................27