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 theref
2、rom, 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 2010 SAE International All rights reserved. No part of this publication ma
3、y 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: +1 724-776-4970 (outside US
4、A) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/J1294_201009SURFACEVEHICLESTANDARDJ1294 SEP2010 Issued 1980-04 Revised 2010-09Superseding J1294
5、 JUL2004 Ignition DistributorsMarine RATIONALEScope Added note Section 2 Editorial changes to contact information Section 5.1 Restored missing text after the word (Secondary) 1. SCOPE This SAE Recommended Practice covers distributors used on marine engines. NOTE: This includes devices referred to as
6、 high voltage switches used for distributing high voltage to the appropriate spark plugs but does not contain any crank position sensing function. 1.1 Purpose To provide recommendations and guidelines for the evaluation, design, and testing of distributors to be used on marine engines.2. REFERENCES
7、2.1 Applicable Publications The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply. 2.1.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096
8、-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.SAE J378 Marine Propulsion System Wiring SAE J548-1 Spark Plugs SAE J1128 Low Voltage Primary Cable SAE J1171 External Ignition Protection of Marine Electrical Devices SAE J1191 High Tension Ignition Cable As
9、sembliesMarine Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1294 Revised SEP2010 Page 2 of 62.1.2 Federal Publication Available from the U.S. Government Printing Office, Washington, DC 20402-
10、9320, Tel: 202-512-1800, http:/bookstore.gpo.gov. Also available at http:/www.uscgboating.org.U.S. Coast Guard Standard 33 CFR 183, Subpart I, Section 183.410 (Ignition Protection) 3. DEFINITIONS 3.1 External Ignition Protection (EIP) The ability to prevent the ignition of a combustible mixture surr
11、ounding the distributor when a combustible mixture within the distributor is ignited. 3.2 Wire The combination of a conductor surrounded by insulation. 3.3 Nipple A molded component to provide electrical insulation of the coil and/or distributor tower terminals. 4. GENERAL The three elements require
12、d to create a fire or explosion are often present in marine engine compartments. They are: an enclosure, a fuel, and a source of ignition. Compliance with this document will minimize the possibility of a distributor used on a marine engine acting as a source of ignition and assure conformance to the
13、 U.S. Coast Guard Standard 33 CFR 183, Chapter 1, Section 183.410. 5. DISTRIBUTOR ENCLOSURE 5.1 The distributor shall meet the requirements of SAE J1171. Openings for the purpose of draining, ventilating, timing, and vacuum advancing must be carefully evaluated and tested to determine their ability
14、to quench an internal combustion of propane and air. Removable covers, plugs, plates, etc., should be avoided due to the possibility of their becoming dislodged, lost, or discarded. Gaskets may be used if secured to one of the mating surfaces. Means used to secure distributor caps shall prevent the
15、cap from lifting off the sealing surface during an internal explosion of a fuel and air vapor mixture. During the test, high-tension (secondary), ignition wiring shall be in place on all distributor cap towers with terminal covering boots as installed during engine operation. 5.2 The fit of distribu
16、tor cap to bowl and distributor bowl drain holes must be carefully evaluated. A drain at the bottom of the bowl is recommended. A safe drain configuration will depend on the size and length of the flame path through the drain. Smaller openings and longer flame paths provide the greatest assurance of
17、 EIP. 5.3 Flame suppressor screening can provide ventilation without loss of EIP. The screened area, the screen mesh, and the number of layers of screening can be varied to provide a safe ventilation method. Screening shall be securely held in place and of corrosion resistant composition such as bra
18、ss or stainless steel. If the distributor housing is painted or otherwise coated, the function of the screening must not be impaired. 6. INSULATION 6.1 The available voltage which exists at a distributor is fully capable of igniting a mixture of gasoline and air. The voltage must be contained within
19、 the insulation system of the distributor towers, wires, and nipples. 6.2 Distributor cap material must meet the tests described in Appendix A. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J12
20、94 Revised SEP2010 Page 3 of 66.3 All single exposed low voltage leads 180 mm or longer in length must be SAE No. 16 gauge minimum, multiple wires enclosed in a sheath of loom may be 18 gauge. Those under 180 mm must be SAE No. 18 gauge minimum. All exposed low voltage leads must meet SAE J378 and S
21、AE J1128. 7. TOWER CONNECTIONS 7.1 Terminal connections and nipples which are initially secure have the greatest potential of remaining in place during service. 7.2 See Figures 1 and 2 for tower configurations. Tower cable terminations and nipples shall be in accordance with SAE J1191. A locking tow
22、er terminal configuration is required. Tower connections must be of nonferrous material. Nipples must be designed so that they do not touch the cap at base of tower before seating. 7.3 New tower connections must meet a minimum of 27 N pull-off force along the tower axis when installed with nipples.F
23、IGURE 1 - TYPICAL TOWER CONFIGURATION FIGURE 2 - TYPICAL TOWER CONFIGURATION Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1294 Revised SEP2010 Page 4 of 68. NOTES 8.1 Marginal Indicia A chang
24、e bar (l) 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 previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including
25、technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. PREPARED BY THE SAE MARINE ELECTRICAL SYSTEMS COMMITTEEOF THE SAE MARINE TECHNICAL STEERING COMMITTEE Copyright SAE International Provided by IHS under license with S
26、AENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1294 Revised SEP2010 Page 5 of 6APPENDIX A A.1 DISTRIBUTOR CAP TESTS A.1.1 Arc Resistance Test A.1.1.1 The high voltage test source shall be arranged approximately as shown in Figure A1. The cap shall be set up
27、 as shown in Figure A2. Average secondary spark current should be 1.5 mA 0.1 mA. FIGURE A1 - HIGH VOLTAGE SOURCE FIGURE A2 - ARC TEST SETUP A.1.1.2 Arcing shall be maintained for 30 s without the tested surface becoming conductive as indicated by a marked increase in average secondary spark current,
28、 the disappearance of all or part of the original arc, or the origination of flame. A.1.2 High Temperature Resistance Test A.1.2.1 Condition the distributor cap and bowl (assembled) in a circulating air oven at 150 C 2 C for 30 min. A.1.2.2 Using a megohmeter capable of reading at least 1 x 106M and
29、 with an internal test voltage of 500 V, the resistance between two adjacent inserts and between an insert and the housing (bowl) shall not be less than 100 M with the cap at 150 C 2 C. Both resistance measurements must be made within 30 s of removing from oven. Copyright SAE International Provided
30、by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1294 Revised SEP2010 Page 6 of 6A.1.3 Wet Internal Resistance Test A.1.3.1 Expose the distributor cap to 100% relative humidity for 24 h. Shake cap vigorously to remove excess moistur
31、e and allow to dry at room temperature for 1 h. A.1.3.2 Using a megohmeter as in A.1.2.2, the insert-to-insert and insert-to-bowl insulation resistance shall not be less than 500 M.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
