1、A-A-50h27 = 9999974 OLbb53Y 707 mm-j A-A-50627 9 February 1995 COMMERCIAL ITEM DESCRIPTION BELL, ELECTRICAL, SHIPBOARD The General Services Administration has authorized the use of this commercial item description for all Federal Agencies. 1. Abstract. This commercial item description covers various
2、 types of bells for alarm and signalling purposes on naval ships. 2. Salient characteristics. 2.1 Mountinq. Bells shall be two- or three-point vertically mounted as specified on figure 1. Mounting shall be as specified (see 6.1). 2.2 Enclosure. Bells shall be dripproof, watertight, or explosionproof
3、 as specified (see 6.1). Enclosure shall be tapped at the bottom for conduit or cable entrance. 2.2.1 DripDroof enclosure. An enclosure in which the openings are so constructed that drops of liquid or solid particles falling on the enclosure at any angle not greater than 15 degrees from the vertical
4、 either cannot enter the enclosure, or if they do enter the enclosure, they will not prevent the successful operation of, or cause damage to, the enclosed equipment (see IEEE 45). Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this
5、 document should be addressed to: Commander, SEA 03R42, Naval Sea Systems Command, 2531 Jefferson Davis Hwy, Arlington, VA 22242-5160 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. AMSC NIA FSC 6350 DISTRIB
6、UTION STATEMENT A. Approved for public release; distribution is unlimited. Licensed by Information Handling ServicesA-A-50627 9999974 0366535 643 A-A-50627 v TWO-POINT MWNTtNC 3 PL FIGURE 1. MountinP dimensions. 2 Licensed by Information Handling ServicesA-A-50627 9999974 0166536 58T W A-A-50627 2.2
7、.2 WatertiPht enclosure. An enclosure constructed so that a stream of water from a hose not less than 25.4 millimeters (nun) in diameter under a head of 11 meters (m) from a distance of 3 m can be played on the enclosure from any direction for a period of 15 minutes without leakage. The hose nozzle
8、shall have a uniform diameter of 25.4 mm (see IEEE 45). 2.2.3 ExDlosionDroof enclosure. Explosionproof enclosures shall be approved for operation in accordance with NFPA 70, class 1, group D, division 2, hazardous areas. 2.2.4 Groundine and bondinq. Metallic enclosures shall be provided with a stud
9、for grounding and bonding. of the enclosure or any exposed metallic components shall be zero ohms when measured with a high quality ohmmeter. of the enclosure when viewed from the front of the bell. Resistance between tip of the stud and any point The stud shall be placed on the left side 2.3 Electr
10、ical isolation. Electrical components shall be electrically isolated from the enclosure or any exposed metallic components. Electrical isolation shall be 100 megohm or greater when measured with a high quality, 500-volt megger. 2.4 Tyes. Bells shall be of the following types: Size OUtDUt 76.2 mm 73
11、decibel (dB) 203.2 mm 85 dB Cowbell 85 dB Sound pressure output shall be based on a reference of 20 micropascal (pPa), and shall be measured at a distance of 3 m from the bell in accordance with ANSI S1.13. 2.5 Construction. Construction shall be such that no special tools are required for disassemb
12、ly or reassembly. 2.6 Power. Operating voltages and frequencies shall be as specified (see 6.1). Operating voltages shall be 6, 12, 24, 115, or 440 volts direct current or root mean square (rms) plus or minus 15 percent and operating frequency shall be 60 or 400 hertz (Hz) plus or minus 5 percent. 2
13、.7 Preservation. Parts shall be of suitable corrosion resistance material or materials treated in a satisfactory manner to render them adequately resistant to corros ion. 3. Oualitv assurance provisions. 3.1 Contractor certification. The contractor shall certify and maintain substantiating evidence
14、that the product offered meets the salient characteristics of this commercial item description and that the product conforms to the pro- ducers own drawings, specifications, standards, and quality assurance practices. The Government reserves the right to require proof of such conformance prior to th
15、e first delivery and thereafter as may be otherwise provided for under the provisions of the contract. 3 Licensed by Information Handling ServicesA-A-5 O b27 W 9999974 OLbb537 4Lb A-A- 50627 3.2 Regulatory requirements. The offerer/contractor is encouraged to use recovered materials in accordance wi
16、th Public Law 94-580 to the maximum extent practical. 4. Preservation. Dackaging. - packing. labeling. - and markinq. The preserva- tion, packaging, packing, labeling, and marking shall be as specified in the contract or order. 5. CID based Dart identification number. The following part identificati
17、on numbering procedure is for Government purposes and does not constitute a require- ment for the contractor. A-A-50627 - 2E344A6 Example of part identification. I Variable characteristics 2 = two-point mounting E = enclosure type 3 = 76.2 mm bell A = alternating current 6 = operating frequency 44 -
18、 operating voltage CID number Designated commercial item description (CID) 6. Notes. 6.1 Accwisition requirements. Acquisition documents must specify the following: (a) Mounting. 2 = Two-point 3 = Three-point D = Dripproof W = Watertight E = Explosionproof 3 = 76.2 IIUII 8 = 203.2 IWI C - Cowbell 06
19、 = 6 12 = 12 24 - 24 11 = 115 44 = 440 (b) Enclosure. (cl Type. (d) Power. D - Direct current A = Alternating current (rms) 6 = 60 HZ 4 - 400 HZ 4 Licensed by Information Handling Services A-A-50627 W 9999974 0366538 352 A-A- 50627 6.2 Documents. (a) NFPA-70, National Electrical Code, is available f
20、rom National Fire Protection Association, One Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101. available from American National Standards Institute, 11 West 42nd Street, 13th Floor, New York, NY 10036. board, is available from Institute of Electrical and Electronic Engineers, Inc., 445 Hoes
21、Lane, P.O. Box 1331, Piccataway, NJ (b) ANSI S1.13, Methods for Measurement of Sound Pressure Levels, is (e) IEEE 45, Recommended Practice for Electric Installations on Ship- 08855-1331. CIVIL AGENCY COORDINATING ACTIVITY: GSA - FSS Preparing activity: Navy - SH (Pro j ec t 6350 - 0137) 5 Licensed by Information Handling Services
