Linear Power Supply - Basic Properties, Terminology, and Theory
What is a Linear Power Supply?
Linear Power Supply exist to provide four separate and distinct functions:
- Change the output to a different voltage level than the input (step up or step down)
- Rectify ac into dc
- Isolate the output from the input
- Stabilize the output against the influence of:
- Source changes (source effect)
- Load changes (load effect)
- Temperature changes (temperature effect)
- Passage of time (time effect or drift)
Linear power supplies are about 50% efficient. Only the smallest linear power supplies are capable of being securely mounted to a DIN Rail. Linear power supplies are still popular today because they provide very tight regulation (.01% typically), almost perfectly clean DC, fast transient response and their low component count helps provide a lower material cost for its user. Linear power supplies are typically open frame because of the excessive heat dissipation from their low efficiency.
DC Power Supply Selection Process
- Gather the required information
- Input voltage and frequency
- Number of outputs
- Voltage of each output
- Amperage of each output
- Peak loading of each output
- Battery Backup
- Determine which models meet all of the required specifications
- Check power supply mounting style, connections and physical size to ensure application suitability
- Check for applicable safety approvals for the country and application the power supply will be used in
- Discrete manufacturing machine diagnostics and controls
- Oil platform monitoring and control in the petroleum industry
- Central and remote water and wastewater control panels
- Monitoring and control panels for local facilities/air handling equipment
- Tire manufacturing mixing and building processes
- Industrial and commercial power house controls; building HVAC controls
- Material handling and palletizing monitoring and control
- Automotive press and machine parts controls
Linear power supplies are available in a wide variety of outputs and inputs. Select from 1-4 outputs, 5-265 VDC outputs and 100-240 VAC inputs to fit your application.