Abstract: A temperature sensor located at a region being monitored controls an output switch that in one position when ambient temperature is below a predetermined temperature applies current to only a first loop circuit and in another position when ambient temperature is at or above the predetermined temperature applies current to only a second loop circuit. Currents in the first and second loop circuits are measured by ferrods to determine whether an over-temperature condition at the region monitored has taken place. An alarm circuit connected to outputs of the ferrods generates an alarm signal in response to a negative transaction of current in the first loop circuit or a positive transition of current in the second loop circuit. A failure in either loop circuit accordingly is insufficient to disable the system. A solid state timer periodically opens the second loop circuit to repeat the alarm signal when the second loop circuit is closed until corrective action is taken.

Abstract: A vehicle data processing system is provided which, even if an on-vehicle data processor such as a navigation system or the like is not active, can input the necessary data into the system at an operator's home or the like. A vehicle includes a data processor and an input unit is independently located in the operator's home or other place. Data of destination and the like inputted into the input unit are transmitted to an information center wherein they are stored in a storage unit. When a sensor in the information center senses that the data processor on the vehicle has become active, the input data are transmitted from the input unit to the data processor.