17. (1) The meetings of the Board and the Executive Committee shall be held at such times and at such places as may be prescribed by rules: Provided that until rules are made in this behalf such meetings shall be convened by the Chairman of the Board or the Committee, as the case may be. (2) To constitute a quorum at a meeting of- (a) the Board, not less than three Directors shall be present; (b) the Executive Committee, not less than two members shall be present. (3) At a meeting of the Board or of the Executive Committee, each Director or member of the Committee, as the case may be, shall have one vote, and in the event of equality of votes the Chairman shall have a casting vote. (4) No Director shall vote on any matter relating to an industrial concern in which he is directly or indirectly interested. (5) If for any reason the Chairman is unable to be present at a meeting- (a) of the Board, a Director other than the Managing Director authorised in writing by the Chairman shall preside at that meeting and in default of such authorisation the Directors present may elect a Chairman to preside at that meeting;(b) of the Executive Committee, a member authorised in writing by the Managing Director shall preside at that meeting and in default of such authorisation the members present may elect a Chairman to preside at that meeting.