ALTROZ SERVICE MANUAL

ELECTRICAL 46 Auxiliary combustion control device The air-fuel mixture self-ignition points are mainly influence by two factors: pressure & temperature inside the combustion chamber. The temperature control in all those condition in which the combustion chamber is relatively “cold” (i.e. during cut-off or during post-start) may improve the reduction of ignition delay with large benefit in terms of emission & combustion efficiency. Auxiliary Power Management device The total power dissipation of glow plug is not negligible (it may vary from 240W to 750W according with glow plug characteristics). In some cases, it may be useful to increase the engine load operating point in order to achieve higher exhaust temperature (e.g. in order to start the regeneration of diesel particulate filter). The glow plug activation in this condition may help either directly, increasing combustion temperature indirectly increasing engine load as required. The features of modern Glow plug Interface unit must allow the EMS to operate in all of above conditions with possibility to choose the driving method & parameter optimization. Command & feedback Signal Description: Command signal: Control unit with voltage (12V) supplies the glow plugs. The glow plug temperature is controlled by ECU through a function stored in memory, which links glow plug temperature with the duration of heat signal (12V). Feedback Signal: Feedback signal given by glow plug controller to EMS ECU. Glow plug informs the EMS ECU what the command given by ECU is followed. Circuit Diagram: Normal operating Mode The diagram show the proceeding of the signals in the function of time during the phase of pre or post heating during normal functioning condition. Application: The device driven by ECU system with a diagnosis protocol EOBD (European On Board Diagnose) drives & checks the operating state of each glow plug during pre & post heating phases of diesel engine made by 3 cylinders. The operating mode is controlled by wiring harness through command & feedback. A protection for high current & overload voltage is integrated & it’s supplied by the control system.