SAE J 1171-1977 External Ignition Protection of Marine Electrical Devices.pdf

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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 ther

2、efrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2016 SAE International All rights reserved. No part of this

3、publication may 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: +1 724-776-49

4、70 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/standards.sae.org/J1171_201609 SURFACE VEHICLE RECOMMENDED PRACTICE J1171 SEP2016 Issued 1977-09 Revised 1982-08

5、Reaffirmed 2016-09 Superseding J1171 MAR2011 External Ignition Protection of Marine Electrical Devices RATIONALE J1171 has been reaffirmed to comply with the SAE five year review policy. 1. ScopeThis SAE Recommended Practice covers all electrical devices suitable for use in marine enginecompartments

6、 and fuel tank spaces.1.1 PurposeTo recommend a test procedure for certifying the External Ignition Protection of electrical devicesused on boats.2. ReferencesThere are no referenced publications specified herein.3. GeneralA device shall not produce combustion by excessive external surface temperatu

7、re or by aninternally generated arc. Reproducible test procedures are necessary to ensure that neither condition cancause external ignition when the particular electrical device is being operated.In the first case, which involves excessive external surface temperatures, a test procedure includes ope

8、rationfor a minimum time at a higher-than-rated system voltage (or current) level with a limiting external surfacetemperature value. This should assure that such a device is acceptable for use in an engine compartment orfuel tank space. This test procedure is detailed in Section 4.In the second case

9、, which involves devices containing parts capable of arcing, two test approaches arenecessary since such devices may be either sealed or non-sealed. Those that are sealed are External IgnitionProtected by the fact that a combustible mixture cannot enter the void in which the arc occurs. Therefore, t

10、hetest of sealed devices is a test of the seal integrity. This test is detailed in Section 5.Non-sealed devices are External Ignition Protected when tests demonstrate that ignition of a combustiblemixture within the device does not cause ignition of a combustible mixture surrounding the device. This

11、 will beverified by 50 device explosions with the flammability of the mixture within the enclosing chamber beingchecked by a chamber explosion after each 10 device explosions as detailed in Section 6.The test sequence for any device is:a. Section 4Device Operationb. Section 5Sealed Devicesc. Section

12、 6Non-Sealed DevicesThis is to ensure that any deficiency introduced in the device by the Operation Test Procedure, such as sealdeterioration, etc., can be detected in the following tests.4. Continuous Device Operation to Determine External Surface Temperatures4.1 Electrical devices not rated for co

13、ntinuous operation and wired with manually operated momentary switchesare exempt from this test procedure. This includes devices such as engine cranking motors, propulsion unittrim motors, and other intermittently operated devices.4.2 This test shall be run with the device in an air circulating oven

14、 having an initial temperature of 60 C 2 C(140 F 4 F).4.3 The device shall be operated continuously for a minimum of 7 h in the mode in which it draws its maximumcurrent.4.4 The test voltage supply shall be adjusted to 120% of the nominal system voltage (such as 12 or 115 V).4.5 The maximum allowabl

15、e surface temperature is 200 C (392 F) measured at any point on the devices exterior.5. Method of TestSealed Devices5.1 Equipment DescriptionRefer to Figure 1.FIGURE 1TEST ASSEMBLY (SEALED DEVICES)_ SAE INTERNATIONAL J1171 SEP2016 2 of 75.2 Test Procedure5.2.1 Submerge the device to be tested in a c

16、hamber of water, changing its attitude if necessary so that allpossible sources of leaks are at the top and are 355 mm 15 mm (14 in 0.5 in) below the surface of thewater. Submerged time is 15 min for each attitude change.5.2.2 Observe the device under test carefully during the test duration for a le

17、ak as evidenced by the generation ofa bubble or stream of bubbles.5.2.3 If bubbles are observed coming out of the electrical portion of the device, the devices shall not be considereda sealed device and shall be tested under Section 6.5.2.4 If no bubbles are observed, remove the device from the wate

18、r chamber and dry its exterior.5.2.5 Disassemble the device for internal inspection.5.2.6 If no water is found inside the device, it shall be accepted as external ignition protected. If water is found, itshall be tested under Section 6.6. Method of TestNon-Sealed Devices6.1 Equipment DescriptionSee

19、Figures 2 and 3. Special note should be taken of the pressure-relief lidarrangement.6.2 Device Preparation6.2.1 Provide means of introducing a combustible mixture of propane and air into the device via 150 mm (6 in)minimum length of rigid or flexible tubing having an ID of 1.5 to 6.35 mm (1/16 to 1/

20、4 in), the selection to bebased on the minimum ID that can maintain a test rate which allows a minimum of two device ignitions perminute. The tubing supplying the mixture sample from the device to the analyzer shall have a 1.5 mm(1/16 in) ID and a minimum length of 150 mm (6 in). (Utilizing the mini

21、mum ID minimizes the effect ofreducing the combustion pressure within the device at the time of ignition and maximizes the severity of thetest.) See Figure 2.6.2.2 Devices that do not contain openings large enough to permit the introduction of the mixture at the requiredrate shall have a vent in the

22、 form of a copper tube with a 150 mm (6 in) minimum length installed in thedevice with the free end open to the chamber. The ID of the copper vent shall be the same as that requiredto feed the device.NOTEThe copper material is necessary to assure quenching of the flame before it reaches the end open

23、to the chamber.6.2.3 Devices which are too small for the direct installation of both the tubing feeding the device and that supplyingthe device gas analyzer require a tee fitting to join the tubes from which a single 150 mm (6 in) minimumlength, 1.5 mm (1/16 in) ID, rigid or flexible tubing can then

24、 enter the device. See Figure 3.6.2.4 The device contacts or a separately mounted spark plug or spark plug-like item is required to provide a gapacross which a spark can jump. The gap size need only be large enough to ignite consistently the specifiedmixture. However, where possible, a 2.54 mm (0.10

25、0 in) gap is preferred. The spark gap provided must beinstalled as close as possible to that part in the device from which the arc would normally originate. Electricmotors, for example, must have a spark plug mounted at the commutator end of the motor since it is at thisend that sparks between the b

26、rushes and commutator can occur. The test chamber ignition system shall bea single-shot system to insure that the surrounding mixture is easily ignitable._ SAE INTERNATIONAL J1171 SEP2016 3 of 76.2.5 Confirmation of ignition within the device can usually be detected by the noise produced. If the “po

27、p” or“bang” is not clearly audible, make provisions to check the pressure rise in the device or utilize the observedflash of combustion seen through a 19 mm (3/4 in) maximum length, 6.35 mm (1/4 in) maximum ID supplytubing. See Figure 3. The transparent tube must connect to the device through a hole

28、 large enough totransmit the combustion into the transparent tube without being quenched.FIGURE 2TEST ASSEMBLY (LARGE NON-SEALED DEVICES)_ SAE INTERNATIONAL J1171 SEP2016 4 of 7FIGURE 3TEST ASSEMBLY (SMALL NON-SEALED DEVICES)_ SAE INTERNATIONAL J1171 SEP2016 5 of 76.3 Test Procedure6.3.1 With the de

29、vice in the test chamber, fill the device and chamber with mixtures as follows:6.3.1.1 Test ChamberFill the test chamber with a mixture of 4.75% 0.25% propane to air by volume. This testchamber mixture ratio is to be maintained during all testing cycles.6.3.1.2 DeviceFill the device with a mixture r

30、atio determined by varying the ratio to produce a maximumpressure rise as indicated by the pressure transducer. This mixture ratio shall then be used throughout thedevice testing procedure. Where the smallest practicable pressure transducer cannot be installed due tothe limited space available, a mi

31、xture ratio of 4.25% 0.25% propane to air by volume shall be used andcombustion determined by the flash of combustion seen through the transparent tubing supplying thepropane-air mixture to the device. See Figure 3.6.3.2 After establishing the proper mixture, stop the filling process and ignite the

32、device mixture with the spark.NOTEIf any attempt to ignite the device mixture fails, purge the device and chamber by returning to step6.3.1 and rerun only that cycle. Do not rerun the entire Test.6.3.3 Confirm combustion in the device.6.3.4 Repeat steps 6.3.1 to 6.3.3 nine additional times in succes

33、sion.6.3.5 Ignite the test chamber mixture with the single-shot spark after each 10 device ignitions to confirm that it ishighly combustible.NOTEIf any attempt to ignite the mixture in the test chamber fails, purge the device and chamber andrepeat steps 6.3.1 to 6.3.3 only for that 10 cycle segment

34、of the test procedure. Do not rerun theentire test.6.3.6 Repeat steps 6.3.1 to 6.3.5 four additional times in succession. If no ignition of the test chamber occurs as aresult of the device ignition (step 6.3.2,) the device shall be considered to be external ignition protected.6.4 Special Notes for N

35、on-Sealed Devices6.4.1 CRANKING MOTORSWhen testing cranking motors, the pinion gear must be placed in the position it wouldoccupy when the motor portion is energized. If the motor portion is energized with the pinion retracted andextended, the cranking motor must be tested with the pinion in both po

36、sitions.6.4.2 DISTRIBUTORSModify the distributor rotor contact to increase the spark gap to 2.54 mm (0.100 in). Connectcomponents as necessary to provide a spark across the gap. Install a high-tension lead to any one of theremaining towers and terminate to ground. Align the distributor rotor contact

37、 with this towers electrode.Included in the distributor test shall be five extended-firing cycles. Each extended-firing cycle shall consist ofmaintaining the spark for an additional 5 min after ignition of the distributor mixture as described in 6.3.1 to6.3.3. If the chamber mixture ignites, the dis

38、tributor shall be considered failing.6.4.3 INTRINSIC SAFE DEVICESSee Note 1 in 7.4.7. Marking7.1 Evidence of compliance with the recommended practice shall be indicated by the marking SAE J1171 togetherwith the word MARINE arranged in any suitable manner. If the space is too small for this wording,

39、the wordsmay appear on or in the smallest packaging of the device._ SAE INTERNATIONAL J1171 SEP2016 6 of 77.2 Responsibility for device marking shall be negotiable between the customer and vendor.7.3 Marking should be as permanent in nature as possible.7.4 Service replacement parts that are essentia

40、l to External Ignition Protection should be identified in the devicesparts book as necessary to assure proper part and/or assembly replacement in the field for continuing ExternalIgnition Protection.NOTE 1An electrical device which produces low energy sparks during normal operation may be considered

41、to be an intrinsically safe device. An intrinsically safe device is defined as one in which the electricalpower flow, at the maximum operating condition, is at a sufficiently low level such that the devicecannot, in manner, release an amount of thermal energy capable of igniting gaseous mixture asde

42、fined in 6.3.1.1.Such devices are not normally exempt from testing per this recommended practice for the followingreason:The level of power flowing through any device is dependent on the impedance of the device itself, theimpedance of the shared circuit components, and on the source of electrical po

43、tential. In addition,inductive, capacitive, and voltage variations plus multiple installations, and parallel operation can allchange the energy flow through a device.However, if the parameters of use are known, unvarying, and the maximum energy conditions arestrictly defined, the physical test of su

44、ch a device may be waived. If the absolute maximum releaseof energy, at the sparking members within the device, is no greater than 0.24 mJ, the device will beacceptable for use in explosive atmospheres.PREPARED BY THE SAE MARINE ELECTRICAL SYSTEMS SUBCOMMITTEE OF THESAE MARINE TECHNICAL COMMITTEE_ SAE INTERNATIONAL J1171 SEP2016 7 of 7