Replacement Transformers
Distribution transformers rarely catch the attention of the Operation and Maintenance department. They do not have any moving parts; they cannot jerk or misfire. They do what they have to, day after day, year after year, with a remarkably high level of energy efficiency and reliability. Transformers provide an almost constant quality of service. Their decrease in energy efficiency and reliability is at a very slow rate and generally remains unnoticed. Until, that is, they fail and have to be replaced.
If reliability is the only criteria, replacement of the transformer is the best option. This is especially the case for relatively old transformers (>25 years) for which maintenance measurements have shown that risk of failure has risen substantially above the average.

REASONS FOR A REPLACEMENT TRANSFORMER
- To improve energy efficiency.
- To improve the reliability of supply.
- Because of a change in load profile.
- To comply with environmental and fire safety regulations.
- Reduction of maintenance cost.
VTC WILL MEET YOUR REQUIREMENTS
- We can meet any possible dimension requirement.
- Our engineers will come to your site to take measurements so you get the exact unit you need.
- VTC will even match HV and LV termination so you don’t have to spend extra to change termination dimensions.
- VTC makes replacement easy and worry-free.
- Replacement transformer will fit existing pad.
APPLICABLE STANDARDS
- ANSI - American National Standards Institute
- IEEE - Institute of Electrical and Electronic Engineers
- CSA - Canadian Standards Association
- C57.12.00– Standard General Requirements for Liquid- Immersed Distribution, Power and Regulating Transformers
- C57.12.90 - Standard Test Code for Liquid-Immersed Distribution, Power and Regulating Transformers and Guide for Short Circuit Testing of Distribution and Power Transformers
- C57.93 - Guide for installation of Liquid-Immersed Power Transformers
- C57.98 - Guide for Transformer Impulse Tests
- C57.100 - Standard Test Procedure for Thermal Evaluation of Oil-Immersed Distribution Transformers
TRANSFORMER FEATURES
RANGE
- 1 to 100 MVA
- 15KV to 230KV voltage class
LOADING
- Designed to deliver rated current and MVA in all tap positions
SERVICE
- Outdoor
BASIC IMPULSE LEVEL (BIL)
- Per ANSI standard
COILS
- Aluminum or copper conductor
- Circular or rectangular construction
- Continuous or helical disc
- Barrel wound
Paint
- ANSI 61 enamel on sandblasted surface
- Other colors available
Nameplate
- Stainless steel
- Engraved
Cooling Fluid
- Type II mineral oil
- R-Temp or silicone oil available up to 15 MVA
Gauges and Accessories
- Liquid temperature indicator
- Liquid level gauge
- Vacuum pressure gauge
- Drain valves
- Filter press connections (top and bottom)
- Automatic pressure relief device
- Control wiring in flexible conduit
- Other accessories available
Fluid Preservation System
- Sealed tank or conservator
Cooling Radiators
- Plate type
Bushings
- Cover or side mounted
CUSTOM FEATURES
- Reconnectable windings
- Non-standard impedance
- Epoxy paint in your choice of color
- Demountable radiators with isolation valves
- Galvanized radiators
- Terminal throats and chambers
- Sloping roof
- Multi-stage fan cooling for increased MVA
- Other gauges and accessories
- Shock indicator
- Customer-specific controls and relays
FIELD SERVICE OPTIONS
- Field Installation
- Assembly Onsite
- Hot Oil Vacuum Processing
- Crane Services/Off-loading
- Field Testing
- Onsite Training
VTC HISTORY
- 1971 - VTC established
- 1982 - Current president assumes management
- 1989 - Manufactures first LTC transformer
- 1995 - Opened 2nd manufacturing facility in Chihuahua, Mexico
- 1997 - Achieves ISO 9001 certifi cation
- 2003 - Acquired medium power transformer facility, Pocatello, Idaho
- 2005 - Testing facilities upgraded, enabling “Front of Wave” and “Switching Surge” testing
- 2009 - Added Vapor Phase Drying (VPD) – Pocatello, ID
- 2011 - VTC’s 40th Anniversary
- 2012 - Introduction of VCM (Virginia Control Module) – VTC enters Wind and Solar GSU Pad mount market
- 2013 - Expanded Roanoke to Troutville with a new Metal Fab facility
- 2014 - Added Vapor Phase Drying VPD to Roanoke facility
VTC REPLACEMENT CLIENTS
-
Fluor / Tesoro Wilmington Refi nery
(2) 5 MVA, 13.8 kV transformers
(2) 2 MVA, 13.8 kV transformers -
POWELL / CHEVRON TAHITI PROJECT
(2) 2000 kVA, 6.9 kV transformers
(2) 4000 kVA, 6.9 kV transformers -
SYNCRUDEOIL / TAR SANDS PIPELINE
(4) 5000 KVA, 34.5 kV transformers -
ATLAS PIPELINE - BUFFALO PLANT
(4) 15 MVA, 34.5 kV transformers -
MARATHON OIL - AGILITY PROJECT
(3) 3750 KVA, 15 KV transformers
Products / Applications / services
LIQUID TYPE TRANSFORMERS
-
Ratings
- 300 kVA to 500 MVA
- Up to 500 kV Class -
LTC
- Up to 500 MVA
- Up to 230 kV Class
-
Cooling Fluids
- Mineral Oil, Beta, Silicone,
Envirotemp (FR3), Lumino -
Three Phase Regulators
- Up to 69 kV
-
Fluid Preservation
- Sealed Tank (Standard)
- Automatic Nitrogen System
- Conservator
DRY TYPE TRANSFORMERS     Indoor & Outdoor
-
VPI (Vacuum Pressure Impregnated)
- 300 kVA to 15 MVA
- Up to 35kV Class
- 220ºC Class Insulation
-
UNIClad® Encapsulated Coils
- 300 kVA to 15 MVA
- Up to 35kV Class
- 220ºC Class Insulation
-
Totally Enclosed
Non-Ventilated TENV
- Up to 5000 kVA
- Up to 35 kV Class
INDUSRIAL
- Rectifier Duty
- Paper & Cement Mills
- Steel Mills
- Motor Start
- Fan, Pump & Compressor Operation
- Hoists
- Mining
- Drive Isolation - AC, DC
- Chemical Plants / Ethano
- Oil & Gas - Refineries, Pipelines, Storage, etc
- Zig-Zag Transformer
- Cycloconverter Application
- Dynamic Voltage Restorer
- Unit Substation
- Special Fluid Transformers - Silicone, Envirotemp (FR3), Beta Fluid
- Chemical / Hazardous Environment- Class I, Division II, Group C & D
- Coastal Environment / Offshore
SWITCHGEAR MATCH-UP FOR
- General Electric
- Cutler Hammer
- Siemens
- Square D
- Others
TYPICAL DIMENSIONS FOR LIQUID FILLED TRANSFORMERS
Dimensions and weights are typical and should not be used for design purposes. For exact dimensions and weights, contact the factory. Smaller or matching dimensions may be possible.

