1、_ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2009 SAE International All rights reserved. No part of this publication m
3、ay be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA)
4、 Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SURFACE VEHICLE STANDARD J2121 JUL2009 Issued 1995-04 Revised 2009-07 Superseding J2121 DEC2002 Requirements for Composite Lighting Assemblies Used on Construction and Industrial Machinery RATIONALE This Standard has
5、 format changes in accordance with the SAE Ground Vehicle Format Guidelines Manual, technical corrections, Light Source interchangeability requirement added, and some design-restrictive aspects were eliminated. 1. SCOPE This SAE Standard provides general design performance requirements and related t
6、est procedures for composite lighting unit assemblies, other than signaling and marking devices, used on Earthmoving, Agricultural Tractors, and Road Building and Maintenance off-road work machines as defined in SAE J1116. 1.1 Purpose To provide general guidelines and design parameters for lighting
7、assemblies used on construction and industrial machinery. 2. REFERENCES 2.1 Applicable Publications The following publications form a part of this specification to the extent specified herein. Unless otherwise specified, the latest issue of SAE publications shall apply. 2.1.1 SAE Publications Availa
8、ble from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. SAE J180 Electrical Charging Systems for Off-Highway Work Machines SAE J1029 Lighting and Marking of Construction, Earthmoving Machiner
9、y SAE J1116 Categories of Off-Road Self-Propelled Work Machines SAE J2121 Revised JUL2009 Page 2 of 7 2.1.2 ASTM Publication Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM B 117-90 Standard Test Method
10、of Salt Spray (Fog) Testing 3. DEFINITIONS 3.1 Composite Lighting Assembly A lighting device fitted with a replaceable light source and typically comprised of lens, reflector and holding mechanism, and housing. 3.2 Design Beam Pattern The beam distribution which establishes 90% of the light output.
11、It is defined typically by angular degrees horizontal by angular degrees vertical. 3.3 Design Voltage or Test Voltage That voltage assigned by the burner manufacturer to establish the specifications for current and light output. 3.4 Test Fixture A fixture which simulates the mounting interface of th
12、e lighting unit to a machine. It may be used for the icing and pressure water test. 3.5 Design Life The rated quiescent average life of a burner or light source in hours, at rated voltage on a test stand (the B50 Stand Life). 3.6 Application Voltage The voltage, generated and distributed by the mach
13、ine electrical system, that is applied to the lamp terminals. 4. LIGHT SOURCE REQUIREMENTS 4.1 Interchangeability The light source shall be replaceable with an equivalent light source and acceptable lamp assembly performance be maintained. 4.2 Life Acceptable life is often determined by the applicat
14、ion requirements. These are primarily shock, vibration, voltage transients, and steady-state voltage. The average bench life of the light source shall be mutually agreed upon between lamp manufacturer and machine manufacture 4.3 Steady-State Voltage The control of steady-state voltage can be very im
15、portant in the application of a light assembly (especially tungsten lamps). SAE J2121 Revised JUL2009 Page 3 of 7 For tungsten lamps, the re-rating rules are: a. Rerated Light Power = (V/VD)3.5x light power at VDb. Rerated Life = (VD/V)12x life at VDc. Rerated Current = (V/VD)0.55x current at VD whe
16、re: V = Application voltage VD= Design voltage In order to maximize the life and effectiveness of a lamp, the application voltage should be identical to the design voltage. The application voltage is the result of the following: a. Alternator output voltage which is dictated by the requirements to r
17、e-charge the battery. b. Voltage drops resulting from the various control devices such as switches, circuit breakers, etc., in the lamp circuit. c. Voltage drop in the electrical cables and ground return of the lamp circuit. The application voltage is typically adjusted by selecting the lamp circuit
18、 cable to provide the appropriate resistance and voltage drop. Quiescent life tests shall be performed at the nominal design voltage level within 0.1 V. The voltage shall be measured at the light assembly electrical interface. 4.4 Voltage Transients As shown in Table 1, voltage transients take on ma
19、ny forms depending on their source. Transients can cause immediate failure or significantly shorten the life of the lamp. The system design shall take into account these transients to eliminate or reduce their effect on the life of the light assemblies. TABLE 1 - TRANSIENT VOLTAGES Cause Effect Volt
20、age Regulator Failure 50% over Voltage Jump Starts 100% over Voltage Alternator Load Dump (Disconnect Battery) 12V System: (14+100 e-t/.2) V 24V System: (28+200 e-t/.2) V (t=time in seconds) Inductive Load Transients 200 e-t/.2V (t=time in seconds) Mutual Coupling in Harness 200 e-t/.001V (t=time in
21、 seconds) Accessory Noise 1.5 vpk (50 Hz to 10 kHz) Radio Frequency Interference R F Energy Machine Welding 100% over Voltage SAE J2121 Revised JUL2009 Page 4 of 7 5. OPERATING AMBIENT TEMPERATURE The light assembly shall operate throughout the temperature range of 40 to 85 C. No permanent deformati
22、on or cracking is acceptable throughout this range over the design life of the assembly. 6. MAXIMUM OPERATING TEMPERATURE If contact with the lens or housing is likely due to the lamp mounting location, consideration shall be given to the surface temperatures and the protection that may be required.
23、 7. SHOCK AND VIBRATION Shock and vibration are common in off-road equipment and the following situations are typical: Operating over rough terrain, running into immovable objects, and using the mounted tools as hammers. The shock levels induced and the resulting structural vibrations have a negativ
24、e effect upon light filament life. Light mounting methods and locations should be selected to reduce shock and vibration effects. Both level and frequency are important to the overall life of the light. Lower voltage filaments are more rugged and are better able to withstand shock and vibration. The
25、 test criteria to evaluate the ability of the light assembly to withstand shock and vibration shall be determined and agreed upon by the lamp manufacturer and the machine manufacturer. The test criteria shall define the frequency range, acceleration, length of test in each axis, sweep rate, and the
26、power cycle in order to establish a quantitative value of lamp life for the application. 8. DUST The light assembly shall be sealed to dust and the following dust test shall be used. An initial light power test to measure peak candlepower shall be performed. An enclosure, with a minimal inside dimen
27、sion of 1 m shall contain 15 kg of AC fine dust (as referenced in SAE J180). The light assemblies shall be mounted not closer than 150 mm from any wall in the normal operating orientation toward the bottom of the enclosure. Every 15 min the dust shall be agitated by a fan blower for enough time to c
28、ompletely and uniformly diffuse the dust throughout the enclosure. The dust is then allowed to settle. This test is to continue for 500 h. After the dust test, each assembly exterior is to be cleaned and the peak candlepower determined. The light assembly shall be operable within 90% of its initial
29、value to pass this test. 9. MOISTURE SEALING 9.1 Pressure Washer The light assembly, as installed, shall not accept water internally from a high-pressure washer when operated at 140 bar with a solid cone angle and orifice of 2 mm. The nozzle shall pass not closer than 300 mm from the front surface o
30、f the light during washing while the light is mounted into its test fixture in its proper orientation. 9.2 Rain and Shine The light assembly, as installed, shall be subjected to 100 cycles of rain and shine operation. Each cycle shall consist of 1 h of simulated precipitation of 5.0 mm/h of water fr
31、om one or more solid cone nozzles followed by 1 h where the test sample lamp is energized at rated voltage. After the 100 cycle test, the samples shall be examined. Moisture ingression or corrosion that results in degradation in performance shall constitute a failure. SAE J2121 Revised JUL2009 Page
32、5 of 7 10. FLUID COMPATIBILITY The light assembly shall remain functional and shall not degrade when it comes into contact with chemicals commonly used in off-road machinery. The assembly will be brushed with engine oil, hydraulic and transmission oils, #1 diesel fuel, brake fluid, ethylene glycol,
33、and phosphatizing agents at room temperature. The samples shall be completely brushed eight times with each fluid with a 1 h interval between each brushing. The samples will be allowed to stand 16 h minimum in this condition. At the completion of this period, rinse, air dry, and then test the light
34、assemblies with criteria being 90% of its initial peak light output and no discoloration or degradation. 11. ICING The light assembly shall show no damage when allowed to ice over. The test procedure for each 24 h cycle is shown in Figure 1. The light assembly may be mounted into its test fixture fo
35、r this test. The light assembly and test fixture shall be turned upward to aid in distributing the water over the exterior surface. The light assemblies shall be subjected to ten of these 24 h cycles. Any assemblies found with cracks, open seams, or other damage shall be cause for failure of this te
36、st. FIGURE 1 - ICING TEST PROCEDURE 12. ILLUMINATION PERFORMANCE The light output or performance is a function of the intended design and application. The illumination effects in any given application are very subjective and need to be quantified by measurable features. Measurable parameters of this
37、 performance are beam pattern intensities, measured in candela and displayed as photometric test point candela or as an iso-candela curve, and ground surface beam distribution illumination measured in lux and displayed in an iso-lux surface area plot. General desirable qualities of all beam pattern
38、distributions are smooth, even lighting gradients throughout the entire beam pattern. This will eliminate hot spots, voids, and stria which can cause false cuing or poor acuity to the operator of a machine using this light pattern. To allow for the optimum flexibility in providing lighting pattern t
39、hat perform specific illumination objectives, an agreement between the supplier and customer should be reached as to the desired characteristics of the lighting pattern and method of measurement. Two methods of depicting lamp output are shown in Figure 2 (vertical plane) and Figure 3 (horizontal or
40、ground plane). SAE J2121 Revised JUL2009 Page 6 of 7 FIGURE 2 - ISO-CANDELA CURVE FIGURE 3 - ISO-LUX CURVE 13. CORROSION ENVIRONMENT (AS REQUIRED) Corrosion environments exist throughout the world where salt air and salt water splash, and immersion of the light assembly may occur. Where operation in
41、 a salt-free environment is intended, this test may not be applicable. It is recommended that grounds be isolated from the structure because positive voltages tend to accelerate the corrosion process. Consideration shall be given to environmental protection for the electrical connections. To determi
42、ne the ability of the light to withstand corrosive environments, a 5% salt spray (fog) test is required (Reference ASTM B 117). The corrosion test shall extend to 96 h with the lights powered to the design voltage 12 h on and 12 h off. The chamber ambient temperature during the test shall be 35 C 1
43、C. The pH of the solution shall be maintained between 6.5 and 7.2. Interconnecting harnesses, connectors, and grounding must be representative of the design. SAE J2121 Revised JUL2009 Page 7 of 7 After the completion of the test, the light assemblies shall be examined for function, material, deterio
44、ration, seal integrity and oxidation of the metals. Electrical connections shall not degrade relative to their condition at the start of the test. 14. WATER SUBMERSION (AS REQUIRED) Some applications may have a water submersion requirement. In building or maintaining docks or dikes, some submersion
45、of lights may occur. In those applications, a submersible light is required. The light assembly shall be energized for 1 h at its design voltage, and then submerged in water. After 1 min, the power shall be removed and the light shall be allowed to cool another hour. The light assembly shall be remo
46、ved from the water and the outer surfaces dried. If there is no sign of water on the inner surfaces of the light, the light assembly is acceptable to submersion. 15. SERVICEABILITY/ADJUSTABILITY Lamps, as installed, shall provide serviceability and adjustability as required for the application. Cons
47、ideration must be given to bulb/burner replacement as well as ease of adjustment when installed. 16. NOTES 16.1 Marginal Indicia A change bar (I) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the pr
48、evious issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, or in documents that contain editorial changes only. PREPARED BY THE SAE OPERATOR PROTECTION TECHNICAL COMMITTEE SC3LIGHTING AND MARKING
