The TDK-Lambda brand CUS400M ac-dc power supply series in the industry standard 3×5-in footprint. Rated at 400 W with forced air, the series can continuously deliver 250 W, with peaks of up to 400 W for 30 minutes when convection or conduction cooled. This is considerably longer than many products on the market. These power supplies are ideal for applications with occasional peak demands, including hospital beds, dental chairs and other motor driven products.
The CUS400M meets curve B conducted and radiated EMI in either a Class I or Class II (double insulated) construction, 
without the need for external filtering of shielding. The CUS400M series accepts an 85 to 264 Vac input and is available with 12-V and 24-V outputs initially, with 15, 19, 28, 36 and 48-V models following shortly. A 5-V 2-A or 12-V 0.83-A standby voltage, remote on/off, remote sense, dc Good and ac Fail signals can be specified as an option.
The power supplies are available with multiple mechanical configurations. Open frame, metal baseplate, U channel and enclosed models are in production now, with the top fan version later in the year. The open frame CUS400M measures 77.5x 128×39.5 mm (W x L x H). The operating ambient temperature is -20°C (-30°C start-up) to +70°C, derating linearly above 50°C to 50% load.
The CUS400M has an input to output isolation of 4,000 Vac (2 x MoPP), an input to ground isolation of 1,500 Vac (1 x MoPP) and an output to ground isolation of 1,500 Vac (1 x MoPP) for suitability in B and BF rated medical equipment. The leakage current is <250 µA and touch current is <100 µA. The maximum operating, transportation and storage altitude is 5,000 m. Safety certifications include IEC/EN/ES 60601-1, IEC/EN/UL 62368-1 and IEC/EN/UL 60950-1 with CE marking for the Low Voltage, EMC and RoHS Directives. The units also comply with EN 55011-B and EN 55032-B conducted and radiated emissions (Class I and II), and meet the EN 61000-3-2 harmonics, IEC60601-1-2 Edition 4 and IEC 61000-4 immunity standards.
More information on the full 30 to 1,500-W rated CUS-M series, including distributor inventory, can be obtained from the TDK-Lambda Americas website at www.us.lambda.tdk.com.
