This part of IEC 61204 specifies the safety requirements for switch mode power supply (SMPS) units providing d.c. output(s) with or without auxiliary a.c. output(s) operating from a.c. or d.c. source voltages up to 1 000 V a.c. or 1 500 V d.c. (See exceptions in 1.2). This product standard covers both stand-alone and component SMPS as defined in this document. SMPS, which comply with this standard, satisfy the requirements of SMPS for use in or with other equipment, when referenced in such end product standards. This standard also covers DC-DC converters. D.C. power and distribution equipment which provides, distributes, monitors, and controls isolated secondary circuit power to other equipment typically used in communication applications (refer to Annex AC). Equipment which is within the scope of this annex consists of some or all of the following: " Distribution panelboards, powerboards, disconnects, and overcurrent protective devices. " Control and monitoring equipment. " Assemblies consisting of: racks, shelves, and ENCLOSURES which could contain any of the above components, interconnecting hardware, POWER SUPPLIES (such as rectifiers, converters, and inverters), BATTERIES, and any other related peripheral devices. Where no standards exist, use of this standard for other applications is not precluded.