Abstract: In a system including a power supply, such as a rectifier, which supplies power to a load and in which a back-up battery is arranged between the power supply and load, a current controller is configured to control the recharging current supplied to the back-up battery. The current controller includes a variable resistance which is altered dependent upon whether more or less current is to be used for recharging of the back-up battery. The use of the current controller ensures that sufficient current is available for the load during the recharging process, even in a situation where the back-up battery requires a high level of recharging.

Abstract: A power supply system including a thermal current limiting device operating due to high temperatures. At predetermined temperatures, the device acts to incrementally control the output of a power supply. An implementation of the device may be found in a voltage or power regulator wherein a constant output voltage or power is desired. As temperature increases, the power supply system is not switched off, rather current output is adjusted in a controlled manner thereby eliminating the need for the device to be entirely shut down for a time period. A back-up battery is used to provide supplementing current needed by the load.