UNIPOWER has announced additions to its Sigma Series of hot-swap front-ends and rectifiers. The new models, now rated at up to 650W, have the same 1U x 2U profile (40.6 x 83.8mm) and are only 279mm long. They also incorporate a number of features designed to make the power sources easy to use and easy to monitor, particularly when used with the customer friendly 19” shelf. At just 0.95Kg (2.05lbs ), they are also among the lightest units available today. Available as front-ends or rectifiers, the modules operate from a universal input voltage from 85 to 264VAC and provide output voltages of 12, 13.6, 24, 27.2, 48 or 54.4VDC. An isolated 5V, 100mA standby output is included. Maximum output power per module is between 300 and 650W which equates to a power density of up to 11.2W/in³. An ORing diode on the output is standard.