This document specifies safety, design, construction and performance requirements and testing for electronic fuel/air ratio control (FARC) systems. Systems can include sensors, mechanical actuators and motors/blowers that make up the complete system. Systems can be described as:
closed loop fuel/air ratio control systems (ERC), see 3.1.1;
closed loop fuel/air ratio trim systems (ERT), see 3.1.2;
fuel/air ratio supervision systems (ERS), see 3.2.
NOTE 1 Throughout this document, the word “system” means “FARC control and system components”.
These systems are intended for use with burners and appliances that burn gaseous or liquid fuels. This document describes the procedures for evaluating these requirements and specifies information necessary for installation and use.
This document applies to the inherent safety of the system, to the declared operating values, operating times and operating sequences if they are associated with FARC safety and to the testing of FARC systems used in, on or in association with appliances.
NOTE 2 The documents for burners, appliances or processes which use ERC, ERS or ERT can override the requirements of this document.
This document prescribes testing requirements in addition to the relevant standards for integrated devices or components (e.g. actuators) to ensure safe operation of the FARC system.
If no part 2 standards in ISO/TC 161, Controls and protective devices for gaseous and liquid fuels, or IEC/TC 72, Textile machinery and accessories, exist, then IEC 60730‑1 is considered.
NOTE 3 Supplemental or modified requirements and tests and evaluations can be needed for ERC, ERS or ERT systems for conformance with relevant burner, appliance or process standards. Conformance of an ERC, ERS or ERT with this document does not imply that such systems or components thereof are acceptable for use on an appliance without supplemental tests of the control system applied to the particular appliance to meet the requirements of the relevant burner, appliance or process standard(s).
This document applies to electronic fuel/air ratio control systems that can be tested independently or as a system or as part of an appliance or as part of a burner.
This document does not cover burner control function like e.g. burner ignition, flame supervision and fuel shutoff.
ISO 23552-1