Howard HI-104 Single-Phase Pad Transformer - Manual (Page 4)

Document 2.4.96, Revision 0
March, 2013
4
Single-Phase Pad-Mounted Compartmental-Type Distribution Transformers
Internal Weak-Link Fuse ............................................................................................................................................................17
Bay-O-Net Fuse .......................................................................................................................................................................... 18
Dead-Break Dry-Well Canister Fuse ..........................................................................................................................................19
Internal Partial-Range Current-Limiting Fuse .......................................................................................................................... 20
S&C Arc-Strangler ...................................................................................................................................................................... 20
S&C Fused Switch ..................................................................................................................................................................... 20
Surge Arrester ........................................................................................................................................................................... 20
Internal MOV Surge Arrester ..................................................................................................................................................... 20
Low-Voltage Circuit Breaker...................................................................................................................................................... 22
Magnex Interrupter ................................................................................................................................................................... 22
Other Switching and Fusing Devices ........................................................................................................................................ 23
SECTION 6: OPERATION OF TERMINAL COMPARTMENT, BUSHINGS, GAUGES AND ACCESSORY DEVICES ..................... 24
Hot-Stick Operable Devices .......................................................................................................................................................24
Pressure-Vacuum Gauge ...........................................................................................................................................................24
Fluid Level Gauge and Sight Plug .............................................................................................................................................24
Fluid Temperature Gauge .........................................................................................................................................................24
Drain Valve and Sampling Device .............................................................................................................................................24
Automatic Pressure Relief Valve ............................................................................................................................................. 25
Internal Fault Detector ............................................................................................................................................................. 25
High-Voltage Bushings ............................................................................................................................................................. 25
Low-Voltage Bushings .............................................................................................................................................................. 26
Current Transformers ................................................................................................................................................................ 26
Accessory Brackets ................................................................................................................................................................... 26
Terminal Compartment ............................................................................................................................................................. 26
Single-Door Terminal Compartment ........................................................................................................................................ 26
Double-Door Terminal Compartment ........................................................................................................................................27
Other Accessory Devices ...........................................................................................................................................................27
SECTION 7: MAINTENANCE AND REPAIR .....................................................................................................................................28
Periodic Inspection.................................................................................................................................................................... 28
Inspection Checklist .................................................................................................................................................................. 28
Electrical Tests .......................................................................................................................................................................... 29
Exterior Paint Finish .................................................................................................................................................................. 30
Fluid Leaks ................................................................................................................................................................................ 30
Audible Sound Level.................................................................................................................................................................. 30
Low-Voltage Circuit Breaker.......................................................................................................................................................31
Magnex Interrupter ....................................................................................................................................................................31
Other Accessory Devices ...........................................................................................................................................................31
Sampling and Testing the Fluid ................................................................................................................................................31
Filtering the Fluid .......................................................................................................................................................................31
Removing or Lowering the Fluid ................................................................................................................................................31
Filling with Fluid .........................................................................................................................................................................31
Opening the Transformer Tank ................................................................................................................................................ 32
Torque Guidelines ..................................................................................................................................................................... 33
Additional Maintenance Instructions ...................................................................................................................................... 34
Repair Parts .............................................................................................................................................................................. 34
Warranty Claims ....................................................................................................................................................................... 34
Tables
Table 1: Torque Guidelines for External Cabinet Fasteners ................................................................................. 33
Table 2: Torque Guidelines for External Bushing Mounting Hardware ................................................................ 33
Table 3: Torque Guidelines for External Bushing Terminal Connections ............................................................. 33
Table 4: Torque Guidelines for Accessories ........................................................................................................... 34