Com-Fab, Inc.- Subbase Tanks, Generator Enclosures & Generator Trailers

Products & Specifications

Subbase Tanks

All tanks are custom built to meet customer requirements.

Features on All Standard Tanks

-Steel tank with baffles

-10 gauge steel base

-Reinforced 7 gauge side supports with lifting eyes

-Filler neck with cap

-2" normal vent

-Emergency venting per NFPA 30

-Conduit entry

-Mechanical fuel gauge

-NPT suction and return fittings with removable dip tubes

-Primed and painted black

-Drain fitting

-Removable panel for conduit access


-UL 142 Listing Close Top Dike

-UL 2085 concrete protected tank

-Single wall

-Double Wall

-Stand alone tanks

-Custom color

-Electric fuel gauge

-Low level warning

-High level warning

-Overfill protection

-Leak detection alarm

-Lockable fuel cap

-Extended fuel fill

-Fuel heater

-Crossmembers (for oversize tanks)

-Floor plate (for oversize tanks)

-Steps and handrail to meet OSHA requirements

-Spring isolator mounting pads

-Spill/fill alarm

-Spill/fill containment

-Complete mounting before shipping

-Florida DEP approved list (File EQ-386)

Tank Specifications

UL 142 Specification

The intent of this specification is to provide the owner with a "Subbase" type rectangular aboveground UL listed closed top dike double wall fuel storage tank, specifically designed and sized for standby emergency backup generators.

The double wall tank is used when extra protection against fuel leakage to the surrounding environment is desired or required. The double wall tank not only contains fuel leakage from the inner tank, it is also sealed to prevent the entrance of rain and debris.

COM-FAB, INC. manufactures it's double wall tank in two pieces; the inner tank, and the double wall base. The inner tank is made of 12 ga. steel, with 10 ga. baffles... space every 20 inches for added support and rigidity. The tank is completely welded, and pressure tested at 5-7 pig for a minimum of 60 minutes.

The double wall base is made of 10 ga. main rails and 12 ga. top and bottom. There are also 3x4.1 channels below the double wall bottom to separate it from the concrete mounting pad. The double wall base supports all the weight of a generator as well as providing a rupture basin. The weight and vibration carrying part of the base is not mechanically connected to the inner tank, this reduces the risk of fatigue of the inner tank welds. The inner tank and the double wall top are welded together around the tank fittings only, to provide a completely sealed rupture basin. The rupture basin is fully welded, then tested with magna-flux penetrating dye.

The tank comes standard with the following fittings: fill, engine supply, engine return, inner tank drain, rupture basin drain, mechanical gauge, normal and emergency tank vents, and rupture basin vent.


COM-FAB Inc. is UL listed under file MH17856 COM-FAB Inc. is listed as an approved equipment supplier for above ground tanks by The Florida Department of Environmental Protection under file EQ-386

Generator Enclosure

Enclosure Features


-Complete Drop-Over

-Drop-Over to Sub Base

-On Frame


Constructed Of:

-Galvannealed Steel


-Stainless Steel

-Prepainted Aluminum

-Fiberglass Reinforced Plywood (FRP)

Structural Frame

-Door Stops

-Stainless Steel Piano-Type Hinge

-Stainless Steel Hardware

-Adequate Air Intake and Exhaust Flow


-Removable Hinged Doors


-Fixed Blade

-Motor Operated


-Bird Screen

-Insect Screen

Sound Attenuation Package

-Level 1- 10 to 15dba @ 23ft

-Level 2- 20 to 25dba @ 23ft

-Level 3- 30 to 35dba @ 23ft

-Thermal Insulation Package

Exhaust Silencer Support System

-Internally and Externally Mounting Brackets




-Rain Cap

-Electrical and Lighting Packages

-Sherwin-Williams Acrylic Enamel Paint

-Custom Paints Per Request

-Complete Mounting Before Shipping

Tank Specifications

Enclosure Specification

1. The intent of this specification is to provide the owner with a weather enclosure, complete in every detail and requiring no additional field modifications or assembly, except where specifically allowed at the time of purchase. The enclosure is to be accurately dimensioned so as to be in compliance with the National Electrical Code (NEC), and the National Fire Protection Association (NFPA) for clearance of all specified items included therein, and all applicable fire codes for a structure and application of this type.

2. ENCLOSURE - The enclosure shall be formed, sheet steel construction as designed and manufactured by COM-FAB, Inc. The construction shall be of 14 gauge galvannealed steel for all component parts. The enclosure shall be reinforced with tube steel supports and a galvanized structural angle base.

3. DOORS - All doors on the enclosure shall be strategically located in areas as to allow ease of maintenance and allow good access to an visibility of instruments, controls, and etc. The doors shall be fitted with piano-type and flush-mounted, adjustable, keylock latches.

4. AIR FLOW - The enclosure shall be constructed to meet or exceed the generators set manufacturers requirements for air flow. The intake air shall enter the enclosure through a fixed intake louver. The exhaust air shall be discharged through a gravity shutter. The intake openings shall be screened to prevent the entrance of birds.

5. ROOF - The roof of the enclosure shall be constructed and reinforced as to support the weight of the largest commercially available exhaust silencer recommended by the generator set manufacturer, and the weight of 2 maintenance workers. The manufacturer of the enclosure shall provide silencer mounting brackets.

6. FINISH - Upon final assembly, the enclosure shall be primed with a minimum of two (2) coats of rust-inhibiting primer. The final finish shall be a minimum of two (2) coats of acrylic enamel paint.

Generator Trailers

Standard Features

-Adjustable Ball or Pintle Coupler

-Safety Chains

-Front Jack

-Dot Highway Lights

-Steel Tubing Frame

-Heavy Gauge Steel Bed & Fenders

-Bumper with Recessed Lights

-Adjustable Running Gear

-Reflective Tape

-License Plate Mounting Provisions with Light

-Light Cord per Customer's Requirements

-Sherwin Williams Acrylic Enamel Paint

-Radial Tires


-Electric Brakes

-Hydraulic Surge Brakes with Free Backing Brake Axle

-Parking Brake

-20 to 500 Gallon Fuel Tanks

-Single Wall or Double Wall Removable Tanks

-Electric Fuel Gauge

-Mechanical Fuel Gauge

-Low Fuel Warning

-High Fuel Warning

-Electrical Package

-Generator Enclosure

-Voltage Selector Switches

-Power Cable and Plugs Mounted and Wired to Customer Requirements

-Shipping Containers and Chassis for Generator Packages Available

-Extra Tank Fittings

-Heavy Duty Jack

-Front & Rear Adjustable Stabilizer Stands

-Parking Brake

-Combo Hitch

-Spare Tire

-Tool Storage Box

-Cord Storage Box or Rack

Trailer Specifications

Enclosure Specification

1. The intent of this specification is to provide the owner with a road ready generator trailer, complete in every detail an requiring no additional modifications, except where specifically allowed by these specifications.

2. Trailer - the trailer shall be constructed of structural steel as designed and manufactured by COM-FAB, Inc. The frame shall be of 6" x 2" structural tubing with 3" angle supports up to 5000 lbs. GVW, 4" angle supports up to 12,000 lbs GVW, and 6" angle supports up to 24,000 GVW. Standard features include: 12 ga. fenders, 12 ga. deck, ball hitch, safety chains, generator mounting studs, retractable front stand, highway lights, adjustable running gear, and license plate holder. The trailer shall be supplied with a hitch as to the owners specifications. The trailer shall be prewired to allow easy installation of the owner supplied light cord.

3. Fuel tank - the fuel tank shall be constructed of 12 ga. steel, single or double walled, and mounted within the trailer bed. The tank shall not be welded to the trailer. Standard features include: mechanical fuel level gauge, fill, supply, return, vent, and drain. All fittings shall be placed for easy access.

4. Axles - the axles shall be sized to accommodate 120% of the gross vehicle weight. Each axle shall be supplied with wheels and tires to match the weight limit of the axle. The axle shall be supplied with electric or hydraulic surge brakes as to the owners specifications. (Note: Ohio law requires trailers 2000 lbs. and over to have brakes.) The axles shall be manufactured by Dexter Axle or equivalent.

5. Finish - Upon final assembly, the trailer and tank shall be primed with a minimum of two (2) coats of rust-inhibiting primer. The final finish shall be a minimum of two (2) coats of high quality acrylic enamel.

All trailers over 18,000 GVW have electric brakes.

All trailers over 2,000 GVW have brakes

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