Power over Ethernet (PoE) Power supplies

The PALS400 family is primarily intended for use as a front-end for powering dc-dc converters in distributed power systems with PoE applications. They are designed to operate from various ranges of worldwide input voltages with no user adjustments or strapping. The PALS family power supplies are intended to be plugged into or removed from an operating system when used in redundant power configuration. The power supplies provide full rated output power up to 50 °C and include MOVs to protect against input voltage transients. Operation at temperatures up to 70 °C is allowed with derating of output current. Access to interfaces for remote sensing, power supply status, bias voltage (stay alive voltage), and inhibit as well as output power connections is through a connector at the rear of the supply. The AC input, fan, handle, and indicator LEDs are located on the front of the supply. Airflow is from the front (AC connector end) out through the rear (output connector end). Some alarm, monitoring, and control signals are designed to be electrically floating from the main output and can be referenced to the positive or negative output or sense line of the power supply. The output is floating with respect to the chassis and can be used as a positive or negative polarity supply. Alarms and controls are available as either open collector signals or as part of an I2C bus. Active current share is supported.