1.1 The purpose of this specification is to provide details of an enclosure that protects internal equipment from rain, dust, vandalism and other conditions found in an outdoor or otherwise harsh environment.
1.2 The manufacturer must be able, upon request, to produce part numbers on all components for repair purposes. Certificates of compliance may be requested on each cabinet or on any component or part thereof.
2.1 The enclosure(s) will meet or exceed the require- ments of a NEMA rating (Specify either 3R
or 4X) and shall be U.L. listed.
3.0 CABINET CONSTRUCTION
3.1.1 The cabinet and door(s) shall be constructed from 5052-H32 sheet aluminum alloy which
has a thickness of 0.125 inch. Alternate material is type 304 stainless steel, mini- mum thickness 14 gauge. (Specifier
must choose either aluminum or stainless steel construction). External welds shall be made by using the Heliarc welding
method; whereas, internal welds will be made by the wire welding method. All welds shall be neatly formed and free of cracks, blow holes and other irregularities. NOTE: There shall be 2 doors front and back.
3.1.2 All inside and outside edges of the cabinet shall be free of burrs.
3.1.3 The cabinet shall be designed with a crowned top to prevent the accumulationof water on its top surface.
3.1.4 The door opening shall be double flanged on all (4) sides which increases strength
around openings and keeps dirt and liquids from entering the enclosure when door is opened.
3.1.5 A door restraint shall be provided to prevent door movement in windy conditions.
3.2.1 The door opening will be a minimum of 80% of the front surface area. Double doors will overlap and utilize a removable center post.
A. The doors shall be furnished with a gasket that satisfies the physical properties as found in UL508 table 21.1 and shall form a weathertight seal between the cabinet and door.
B. The closed door(s) be flush with the side(s) of the enclosure.
3.2.2 The hinges shall be continuous and bolted to the cabinet and door utilizing 1/4-20 stainless steel carriage bolts and nylock nuts.
A. The hinges will be made of 0.075 inch thick stainless steel with a 0.25 inch stainless steel hinge pin.
B. The hinge pin shall be capped top and bottom by weld to render it tamperproof.
C. Hinge leaves will not be exposed externally when the door is closed, but hinge knuckles may protrude. Note: On NEMA type 4X enclosures, all bolt holes shall be gasketed.
3.2.3 The latching mechanism shall be a 3-point draw roller type using an overlapp- ing door design.
A. Pushrods will be turned edgewise at the outward supports and shall be 0.250 inch by 0.750 inch aluminum, minimum.
B. Rollers shall have a minimum diameter of 0.875 inch and will be made of nylon. The center catch shall be fabricated from .187 aluminum, minimum.
3.2.4 An operating handle shall be furnished.
A. The handle will be stainless steel with a 3/4 inch diameter shank.
B. The latching handle shall have a pro- vision for padlocking in the closed position.
3.2.5 A light/alarm switch bracket shall be provided.
4.0 CABINET VENTILATION
(NEMA 3R ONLY)
4.1 A cabinet requiring ventilation shall be provided with louvered vents in the front door with a removable air filter.
4.1.1 Louvers shall satisfy the NEMA rod entry test for 3R ventilated enclosures.
4.1.2 The filter will cover the vents and shall be held firmly in place with bottom and
side brackets and a springloaded upper clamp.
4.1.3 Exhaust air will be vented out between the top of the cabinet and door.
A. The exhaust area shall be a series of .120 x 1.0 inch rectangular holes.
4.1.4 The ventilation plenum area shall be equipped with a removable plate with provisions for mounting an optional fan
4.1.5 Note: On NEMA Type 4, 4X and 12 enclosures, all louver air intake vents on the door and air exhaust vents in the roof overhang are deleted.
4.2 The ventilation system will be designed to handle a minimum of 100 cubic feet of air per minute.
5.0 EQUIPMENT MOUNTING
(Specify as required)
5.1 ADJUSTABLE CHANNELS
5.1.1 The enclosure shall be equipped with two adjustable "C" mounting channels on each side wall of the enclosure, allowing versatile positioning of shelves or panels.
5.1.2 The channel assembly shall provide infinite vertical and horizontal adjustment and not limit the positioning of shelves or panels. All mounting hardware will be furnished (See mounting channel detail).
5.2.1 If equipment is to be shelf mounted, the enclosure shall be provided with shelves fabricated from 5052-H32 aluminum, having a thickness of 0.125 inch.
5.2.2 The shelf depth shall be a minimum of 10.500 inches. The enclosure will have provision for positioning shelves or panels to within four (4) inches of the bottom and to within eight (8) inches of the top of the enclosure.
5.2.3 Shelf mounting flanges shall be a minimum of 1.5 inches.
5.2.4 The front shelf edge will be 1.375 inches to increase available shelf space and will be double flanged to increase shelf strength.
6.0 CABINET FINISH
6.1 Unless otherwise specified, the outside surface of the cabinet shall have a smooth, uniform, natural aluminum finish.
6.2 If painted, the following steps shall be taken as a minimum requirement.
6.2.1 The cabinet door and any other parts to be painted will be treated with an iron phosphate coating conversion technique.
6.2.2 After phosphatizing, the parts shall be baked to eliminate any moisture in seams.
6.2.3 The finish coat of a Polyester Powder will be baked at 400-450 degrees F for (10) minutes.
6.2.4 The finish shall be commercially smooth, substantially free of flow lines, paint washout, streaks, blisters and other defects that would impair serviceability or detract from general appearance.
7.0 CABINET MOUNTING
(Specify as required)
7.1 PAD MOUNTED ENCLOSURE
7.1.1 Enclosures intended for pad mounting shall be constructed with the following pattern:
8.0 APPROVED MANUFACTURER 8.1 Cabinet is to be manufactured by APX Enclosures, lnc. or an approved U.L. listed equivalent.