SWITCH GP-PRESSURE 3166890 - Caterpillar

programmable overrun provides capability for the marine end user to adjust the engine's operating characteristics above the rated engine speed. Programmable overrun allows the end user to take a full advantage of the engine's capabilities above the rated engine speed. The engine performance above the rated rpm is limited only by the engine torque curve or the programmable overrun, not by a fixed overrun curve. The operation of the engine is adjustable above the rated speed. This is based on customer's preference, but operation is always below the map for the engine torque for that engine rating.The settings are changed with the use of Caterpillar Electronic Technician (ET).The adjustment of the torque map above rated speed is determined by the programmable break point and programmable high idle. The programmable break point defines the break point speed. This is the speed that the available rack will no longer follow the map for the engine torque. The programmable high idle defines the maximum engine speed that is allowed. The default values for the programmable break point and the programmable high idle will be set to the high idle limit speed for the particular rating being programmed. The programmable break point may be programmed to a value greater than or equal 1600 rpm and less than or equal to the programmable high idle. The programmable high idle may be programmed to a value greater than or equal to the programmable break point and less than or equal to the high idle limit. The high idle limit is the maximum allowable speed for that engine rating (108 percent of rated rpm).When operating above the engine's rated speed, the available rack will follow the torque map until the programmable break point is reached. When operating above the programmable break point, the available rack will follow a straight line interpolation between the programmable break point and a point defined by the programmable high idle and by a minimum rack limit. The engine will operate isochronous when the engine is operating at the programmable high idle and at light load (when rack is below the minimum rack limit).
Illustration 1 g01183095