The DC-DC Converter provides clean 24 VDC power suitable for instrumentation and control networks or process equipment. For operation under the most harsh and demanding conditions, the unit is sealed and enclosed to protect against moisture, shock and vibration. Power from a 12 VDC battery or other source in the range of 6-17 VDC is converted to a 24 VDC regulated output. Input and output isolation is provided. The unit is designed with extremely rugged surge and transient suppression in addition to sustained over/under voltage protection. With a rating of 170 Watts of output power, the DC-DC Converter has a typical efficiency rated at 90%.