KNX Power Supply 640mA
Professional KNX bus power supply with integrated choke delivering 640mA at 29VDC for residential and light commercial KNX installations. Features auxiliary 30VDC output for displays and binary inputs, comprehensive 3-stage overvoltage protection, and intuitive LED status indicators.
Overview
The PS-640 is a professional-grade KNX bus power supply designed to power KNX TP installations in residential and light commercial buildings. Delivering 640mA at the standard 29VDC KNX bus voltage through an integrated choke, this power supply serves as the essential foundation for any KNX system, providing the regulated bus voltage that all KNX devices require to communicate and operate.
Technical Capabilities
The PS-640 provides a regulated 29VDC output after the integrated KNX choke, delivering up to 640mA dedicated to the KNX bus line. An auxiliary 30VDC output (before the choke) is available for powering additional loads such as touch displays, binary inputs, or Elausys Master Actuators that require external power beyond the KNX bus supply.
Total output current is limited to approximately 1.2A with automatic voltage decrease above this threshold, protecting both the power supply and connected devices from overload conditions. The integrated 3-stage KNX overvoltage protection ensures safe operation and guards against transient voltage spikes that could damage sensitive KNX devices.
The power supply operates at 85% efficiency from a 230VAC 50Hz mains input, protected by a user-replaceable 1A time-lag fuse (subminiature 8.5mm, IEC 60127-3). Four LED indicators on the front panel provide real-time status feedback: voltage OK, current limitation active, short-circuit detected, and reset status.
Installation and Configuration
The PS-640 mounts on standard 35mm DIN rail and occupies 6 DIN modules (106mm width). The compact housing measures 106 x 110 x 60mm and is constructed from UL94-V0 flame retardant polycarbonate with IP20 protection rating, suitable for indoor electrical cabinet installations.
Pluggable screw terminals accommodate both mains voltage (15A 500V rated, up to 2.5mm2/14AWG wire) and low voltage connections (8A 160V rated, up to 1.5mm2/16AWG wire). A manual Set/Reset button on the front panel allows for bus reset operations during commissioning and troubleshooting.
No ETS configuration is required as this is a basic KNX component. Simply connect mains power, wire the KNX bus output to your KNX line, and optionally use the auxiliary output for additional device power requirements.
Applications
Residential Installations: The 640mA output capacity supports typical single-family homes with moderate KNX device counts including switches, dimmers, sensors, and actuators on a single KNX line.
Light Commercial Buildings: Small offices, retail spaces, and service apartments benefit from the reliable power delivery and comprehensive protection features.
System Expansion: Use the auxiliary 30VDC output to power Elausys Master Actuators, touch panels, or binary input modules without requiring a separate auxiliary power supply.
Retrofit Projects: The 6 DIN module width fits standard residential distribution boards, making it suitable for retrofit KNX installations.
Compatibility and Integration
The PS-640 complies with KNX Standard V1.0 for basic components and standardized solutions. It integrates with any KNX TP installation and powers all KNX-certified devices. EMC compliance includes EN 61000-4-2, EN 61000-4-3, EN 61000-4-4, EN 61000-4-5, EN 55022-B, and EN 61000-4-11.
For larger installations requiring more than 640mA bus current or multiple KNX lines, consider using multiple PS-640 units with appropriate line couplers, or contact Elausys for higher-capacity power supply options.