A. Q3 Sound Attenuated Enclosure (Walk in / Drop over)
A weather protective sound attenuated enclosure shall be provided allowing at least 28” of clearance on three sides of the engine / alternator except where stricter local codes apply. Enclosure shall be designed to provide a noise reduction of 30dba @ 3 meters on all sides in a free field environment. Enclosure must be provided with three single walk-in doors. One door must also be located directly adjacent to the circuit breaker per NEC. Enclosure shall be constructed entirely of Galvaneal material to prevent corrosion. Enclosure shall be supplied by Wedlake Fabricating, Inc. of Tulsa Oklahoma 918-428-1641, or approved equal.
A.1. Enclosure Construction
1. All walls shall be constructed of formed 14ga. galvaneal panels not more than 24” in width. Panels shall be welded on the interior of the enclosure to prevent corrosion.
2. Walls shall be designed to withstand 100mph wind load.
3. Roof shall be constructed of formed 14ga. Galvanneal and have a min. of 2” pitch from center. A full width 12ga. galvaneal roof support shall be added at each seam and additional supports added as needed to support the roof mounted exhaust system.
4. Doors shall be pre-hung 14ga. galvaneal construction using “Bullet type” lift off hinges. Door frame shall be formed 12ga. galvaneal construction and bolt onto enclosure.
5. All door latches shall be pad lockable freezer type latches with inside panic release.
6. Air intake shall be thru a sound chamber with internal baffles and louvers placed at the control end of the enclosure and designed to provide a maximum .5 pressure drop at 1000fpm velocity.
7. Radiator air discharge shall be 90deg. discharge elbow with internal sound baffles and fixed louvers.
8. All intake and discharge openings will have ½” x ½” wire mesh screen to prevent entry of birds and rodents.
9. Furnish and install all suitable and required hardware for the installation of the exhaust silencer(s) on the roof of the enclosure.
10. Rain gutters shall be provided at the roof line on all four sides of the enclosure. An additional rain lip shall be provided above all doors on enclosures over 96” tall
11. 4” insulation must provide required sound attenuation and meet ASTM E 84 and UL 723 surface burning characteristics.
12. All insulation must be covered by a minimum 2mil thick mylar barrier and the entire interior of enclosure lined with a 22ga. perforated sheet liner with the exception of the doors which will have 22ga. galvanized sheet liners.
13. Weather tight radiator service door(s) shall be provided in the roof of the enclosure for easy access to radiator cap(s).
14. All fixed louvers shall be attached using zinc plated hardware and shall be of framed construction and shall be easily removable for service and replacement.
A.2. Surface Prep and Finish
1. All surfaces shall be thoroughly and completely cleaned per SSPC-SP-3.
2. Chemically clean all surfaces.
3. Caulk all exterior seams with polyurethane sealant.
4. Apply two coats of rust inhibitive primer (2mil DFT).
5. Apply two coats of PPG Amercoat 450H Acrylic Aliphatic urethane finish paint (2mil DFT).
6. Enclosure paint finish to be textured.
7. Color to be determined by customer.
A.3. DC Emergency Lighting
1. Enclosure shall be provided with two 24VDC powered caged vapor proof incandescent lights mounted inside of the enclosure. Both 24VDC lights shall be wired to a one hour timer switch located at the main entry door and powered by the engine batteries.
A.4. AC Electrical package
1. Enclosure to be wired per NEC and equipped with a 120/240VAC single phase load center with a 100amp main breaker and properly sized circuits with breakers for the following accessories:
- Water jacket heater
- Generator strip heater
- Battery charger
- Two GFCI NEMA 5-20R maintenance receptacles mounted inside, located on opposite sides of the enclosure.
- Two 120VAC caged vapor proof incandescent lights mounted inside of the enclosure operated by two 3-way light switches mounted inside at the breaker access door and at single door on opposite side of enclosure.