Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:99:p16
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 99 (pt 16/39)
Character Range: 1197112–1200238

the correct operation of NOx control measures, or for other engine maintenance purposes.

              In addition the dual-fuel warning system may display short messages, including messages indicating clearly the remaining distance or time before the activation of the operability restriction.

              The system used for displaying the messages referred to in this paragraph may be the same as the one used for displaying additional OBD messages, messages related to  correct operation of NOx control measures, or messages for other maintenance purposes.

              A facility to permit the driver to dim the visual alarms provided by the warning system may be provided on vehicles for use by the rescue services or on vehicles designed and constructed for use by the armed services, civil defense, fire services and forces responsible for maintaining public order.

4.4. Malfunctioning gas supply counter
              The system shall contain a counting system to record the number of hours during which the engine has been operated while the system has detected a malfunctioning gas supply system according to paragraph 7.2.

              4.4.1. The activation and deactivation criteria and mechanisms of the counter shall comply with the specifications of Appendix 2.

              4.4.2. It is not required to have a counter as specified in paragraph 4.4., when the manufacturer can demonstrate to the Type Approval Authority (e.g. by means of a strategy description, experimental elements, etc…) that the dual-fuel engine automatically switches to diesel mode in case malfunction is detected.

4.5. Demonstration of the dual-fuel indicators and operability restriction
              As part of the application for type-approval under this Regulation, the manufacturer shall demonstrate the operation of dual-fuel indicators and of the operability restriction in accordance with the provisions of Appendix 3.

              4.6. Communicated torque

              4.6.1. Communicated torque when a dual-fuel engine operates in dual-fuel mode

           When a dual-fuel engine operates in dual-fuel mode:

                  (a) The reference torque curve retrievable according to the requirements related to data stream information specified in Annex 9B and referred to by Annex 8 shall be the one obtained according to Annex 4 when that engine is tested on an engine test bench in the dual-fuel mode;

                  (b) The recorded actual torques (indicated torque and friction torque) shall be the result of the dual-fuel combustion and not the one obtained when operating with diesel fuel exclusively.

              4.6.2. Communicated torque when a dual-fuel engine operates in diesel mode

              When a dual-fuel engine operates in diesel mode, the reference torque curve retrievable according to the requirements related to data stream information specified in Annex 9B and referred to by Annex 8 shall be the one obtained according to Annex 4 when the engine is tested on an engine test bench in diesel mode.

4.7. Requirements to limit Off-Cycle Emissions (OCE) and in-use emissions