The PSM275 is a 24-port, 275-W power supply for switch and PBX applications that can be powered from either wide-range ac input, 90 to 265 V ac, or a single 44- to 57-V dc input. With an external isolation diode, the power supply can be operated in redundant ac or dc configuration. It offers an output of 200 W for power-over-Ethernet (PoE) applications, and 75 W for a 12-V switch. With a dc input, the product can supply up to 375 W or 15.4 W per PoE port. Providing 12 V dc output voltage for switches and 50 V dc per port in PoE, the PSM275-909 can implement eight to 24 ports in a PoE system, making it suitable for applications such as 10/100 Base T Ethernet switches, security systems, VoIP phone systems and blade servers.
The PSM275 has internal power management with programmable port control, power limiting and port prioritization. An RS-232 port lets the user control and monitor operation. Features include power factor correction and full compliance to European and U.S. EMC requirements, all in a 1U size. The product is safety-approved for cUL 60950-1 and TUV EN60950. The PSA275-901 is priced at $95 in OEM quantities. More information is available at wwww.phihong.com/PSM275.html.