Keysight (Agilent) N7909A Advanced Power System – Power Dissipater Unit, 1000 W

The Keysight N7909A is a 1000 W power dissipater unit designed to extend the capabilities of N6900A and N7900A Advanced Power System (APS) power supplies. This module adds current sinking and two-quadrant operation, enabling the APS to absorb and dissipate excess power without standalone operation. It connects via two-wire power and communication links on the rear panel and occupies 1U of rack height at full width.

– Technical Specifications

• Power Dissipation: 1000 W
• Rack Height: 1U
• Rack Width: Full Rack Width
• Connections: Two-wire power connection, communication connection
• Operating Mode: Two-Quadrant (Source/Sink)
• Compatibility: Keysight N6900A and N7900A Series APS Power Supplies

– Key Features

• Extends current sinking from 10% to 100% of rated output current when paired with an APS supply
• Enables continuous sourcing and sinking of current with seamless transitions
• Two N7909A units provide full two-quadrant operation with a 2 kW APS supply; one unit delivers 50% current sinking capability
• Performs down-programming to pull voltage levels when connected to loads with stored energy and large parallel capacitance
• Simulates internal battery resistance when used with APS supplies featuring programmable output resistance

– Typical Applications

• Testing and simulation of battery-powered devices and systems
• Characterization of loads with reactive or stored energy
• Regenerative load testing requiring bidirectional power flow
• Applications demanding extended sink current beyond the base APS 10% capability

– Compatibility & Integration

The N7909A mounts in systems using the N7907A APS rack mount kit, which supports both 1 kW and 2 kW APS supplies alongside the dissipater unit. Multiple N7909A units can be deployed in parallel configurations to achieve higher dissipation requirements and full bidirectional operation across the complete power supply lineup.