ISO INTERNATIONAL STANDARD 20949 First edition 2018-11 Aircraft Smart contactor General requirements Aeronefs-Contacteurs intelligents-Exigences generales Referencenumber IS020949:2018(E) @IS0 2018 2'WVE4246 IS0 20949:2018(E) COPYRIGHTPROTECTEDDOCUMENT IS02018 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting beloworIso'smemberbodyinthecountryoftherequester. ISO copyright office CP 40i: Ch. de Blandonnet 8 CH-1214 Vernier,Geneva Phone:+41227490111 Fax: +41 22 74909 47 Email:[email protected] Website:www.iso.org Published in Switzerland ii @ IS0 2018 - All rights reserved E'eqr(tkijigf'd("WPG.'E"1gpqxc."8"4:226"Ocftkf.Urckp"cn"tkijiu'tgugtxgf+*Ygf"Hgd36"3225<32"WVE"4246 IS020949:2018(E) Contents Page Foreword ..V Introduction. ..vi 1 Scope. 2 Normative references ..1 3 Terms and definitions ..1 4 Generalrequirements .3 4.1 Detail specification sheets 4.2 Materials 4 4.3 Construction .4 4.4 Terminals 4 4.4.1 Main terminals .4 4.4.2 Auxiliary terminals .5 4.5 Enclosures. .5 4.5.1 General .5 4.5.2 Open enclosures .6 4.5.3 Enclosed enclosures (ventilated explosion-proof) .6 4.5.4 Sealed (other than hermetically) enclosures. 6 4.5.5 Hermetically sealed enclosures 4.5.6 Grounding of enclosures 6 4.6 Installation clearances ..6 4.7 Terminal marking. .6 4.8 Terminal covers and barriers .6 4.9 Mounting. 5 Design characteristics .7 5.1 General .7 5.2 Control signal .8 5.3 Status signals for smart contactors .8 5.4 Fail-safe characteristics ..8 6 Operating characteristics .8 6.1 General operating characteristics .8 6.2 Timing sequence. 6.3 Operating voltage 9 6.3.1 General. .9 6.3.2 Pickup voltage 9 6.3.3 Dropout voltage 6.4 Electrical characteristics .9 6.4.1 General. .9 6.4.2 Contact voltage drop. .10 6.4.3 Quiescentpowerdissipation .10 .10 6.4.4 Control signals 6.5 Contact bounce, operating and release time ..11 6.6 Dielectric strength.. .11 6.7 Insulation resistance ..11 6.8 Overload characteristics .12 6.8.1 General. ..12 6.8.2 Trip characteristics with the overload condition ..12 6.8.3 Circuitbreakercompatibility. .12 6.9 Ground Fault Interrupt characteristics .12 6.10 Trip-free characteristics.. .12 6.11 Life .12 7 Environmental conditions and test procedures .13 iii nefnffrtknunf"hnt"nntike'Kninkwun'nh"VneinnnniE*Vi 'cwintkInff