Howard Mobile Power Transformers User Manual

Mobile power transformers, Introduction, Ratings

background image

Copyright © 2011 Howard Industries, Inc.

Howard Industries, Inc.

Laurel, MS 39440

Document No. 2.4.136

Revision: 0

Issued: December 2, 2011



Howard Industries Mobile Power

transformers are specially designed

for use with mobile power systems

and are the ideal choice for applica-

tions requiring step-up transformation

and interconnection with an electri-

cal distribution grid. These rugged

transformers can take all the abuse

a transportable system typically

receives. They are specially designed

and equipped for the rental power

market, with many valuable features

that improve portability and increase

flexibility for use with different grid


Contact the factory or your local

Howard Industries representative for

more information about our Mobile

Power transformer line and about the

many custom solutions we can offer.


Standard ratings for Mobile Power

transformers have been selected to

satisfy typical requirements for mobile

power systems. In addition to these

standard ratings, a wide range of

optional ratings is available to satisfy

any special customer requirement.

Standard capacities: 45, 75, 112.5,

150, 225, 300, 500, 750, 1000,

1500, 2000, 2500, 3000, 3750,

and 5000 kVA

Standard high-voltage rating:

14400 volts delta, with taps at

13800, 13200, 12870, 12470,

12000, and 11700 volts.

Optional high-voltage ratings from

2400 through 19920 volts

Standard low-voltage rating:

480Y/277 volts.

Optional low-voltage ratings from

120 through 600 volts

Standard frequency: 60 Hertz.

Optional frequency: 50 Hertz

Standard Features

Designed and manufactured in

accordance with all applicable

IEEE/ANSI and NEMA standards

Non-loadbreak high-voltage tap

switch with operating handle

located in the high-voltage


Externally clamped porcelain

high-voltage bushings with spade

terminals (live-front construction)

Mounting provisions for lightning

arresters in the high-voltage


Externally clamped epoxy or

porcelain low-voltage bushings

with integral spade terminals

Removable neutral ground strap in

low-voltage compartment

Lifting provisions

Jacking and rolling provisions

Removable steel forklift channels

Removable terminal compartment

and front sill

Tamper resistant removable tank

access cover

Three-point door latching system

with padlock provision and

recessed interlocking pentahead

security bolt

Tank grounding provisions

Welded mild steel tank construction

with mild steel terminating


Mild steel barrier between high-volt-

age and low-voltage compartments

Corrosion resistant hardware

Recessed tank compartment


Domed covers on tank and terminal


Electrostatically applied powder

paint finish with polyurethane top-

coat (ANSI 70 light gray)

Mobile Power Transformers

Three-Phase Pad-Mounted


Catolog Section

Howard Industries, Inc.

ISO-9001 Certified


Three-phase Mobile Power transformer