FAQs

Constant voltage power supplies provide a stable regulated voltage; this means that the output voltage will remain constant regardless of the varying AC input. During operation, the output voltage will be regulated to within voltage tolerance which normally stands at 1-2%.

Constant current, on the other hand, provides a stable output current whilst the voltage can vary. Sunpower's constant current LED power supply range possesses both constant voltage and constant current characteristics. Sunpower's constant current drivers operate at start-up in constant voltage mode. Once the output current rated load is exceeded and it reaches the constant current region, the LED driver will operate in constant current mode. This type of operation allows for direct drive of LEDs and can allow a more flexible system design.

When 2 Power Supplies are connected in parallel, they can share the load if the following steps are taken.

Step 1

Measure the output voltages of each power supply at no-load conditions. For example, check the voltage from Anode1 to Ground on PSU1 and from Anode2 to Ground on PSU2. If the voltages are identical, proceed to Step 3. If there is a discrepancy, proceed to Step 2.

Step 2

Adjust the output voltages to match. Use the voltage adjustment knob (VR), typically marked as ADJUST, on the front panel of the power supply. For instance, if PSU1 shows 24.15Vdc and PSU2 shows 24.25Vdc, adjust one of them so both read the same, e.g., 24.20Vdc.

Step 3

Connect the Power Supply to the end system load and measure the output voltages from A1 to Ground, i.e. Voltage Anode 1 to Ground of PSU1 and Voltage Anode 2 to Ground of PSU2. Ensure that the output voltages are the same even after the 2 Power Supplies are connected to the load. If not, adjust them with the VR available on the front panel. A tolerance of +/-25mV would be acceptable.

Additional Notes:

1) If the output voltage of any Power Supply is higher, it will take the initial load and share the maximum load.

2) If the output voltages are the same, then an approximately equal load current sharing between the 2 Power Supplies can be achieved.

3) The ORing diode must be of an appropriate rating. The rating must be at least 4 times the output load current and at least a reverse voltage rating of 20Vrr.

4) The use of a heat sink is advised to ensure the ORing Diode does not overheat.

5) Recommended product for parallel operation up to 20A: DR-RDN20.

When considering the vertical installation of a power supply, several important factors must be taken into account to ensure that the unit operates efficiently and safely:

1) Check the Manufacturer's Guidelines

Always refer to the manufacturer’s instructions or datasheets first. These documents typically include crucial information on installation orientations and any specific instructions or limitations.

2) Understand the Derating Curve

The derating curve is essential as it shows how the power supply's output capacity changes with temperature and installation orientation. For example, a vertical installation might reduce the maximum allowable ambient temperature, which can affect performance if not adjusted accordingly.

3) Cooling Considerations

Determine if the power supply has a built-in fan or relies on natural convection for cooling. Power supplies with active cooling (fans) are generally less affected by orientation changes. However, those that rely on passive cooling might perform differently when installed vertically due to changes in how heat is dissipated.

4) Ambient Temperature Impact

Installation orientation can affect the thermal properties of a power supply. For instance, some models might have a reduced ambient operating temperature limit when installed vertically. If the model supports forced air cooling, this can increase the ambient temperature tolerance by up to 20%, as effective cooling is more crucial in vertical positions.

5) Physical Stability

Ensure that the power supply is securely mounted to prevent any movement that could disrupt connections or operations. Vertical installations may require additional support or brackets to maintain stability.

6) Accessibility and Maintenance

Consider the accessibility for future maintenance, inspections, and potential replacements. Vertical installations should be planned in a way that allows easy access to the power supply for any necessary servicing without needing to disassemble other components.

By addressing these factors, you can safely and effectively install a power supply in a vertical orientation, ensuring it delivers optimal performance while adhering to safety standards and manufacturer recommendations.

1) Select appropriate converters

Choose two single-output converters that match the voltage and current requirements of your dual-output needs. It's important to verify that each converter can handle the expected load individually.

2) Decide on configuration type

• Series Configuration: Use this method to achieve a higher voltage output by connecting the positive terminal of the first converter to the negative terminal of the second converter. The overall output voltage is the sum of both converters' voltages, suitable for applications requiring a higher voltage than what one converter can provide.

• Parallel Configuration: For increased current output, connect the positive terminals and the negative terminals of both converters together. This setup is ideal for applications needing more current. Ensure the converters are capable of parallel operation and consider using additional circuitry to balance the load.

3) Implement isolation if necessary

If the two outputs need to be electrically isolated from each other, make sure to use isolated converters. This prevents potential grounding issues and ensures independent operation of each circuit.

4) Install protective components

Incorporate fuses, diodes, or circuit breakers as necessary to protect against overcurrent, reverse polarity, and voltage spikes. This step is crucial for maintaining system safety and longevity.

5) Wiring and physical setup

Carefully connect the converters according to your chosen configuration. Secure all connections and ensure that wiring is neat to avoid any accidental shorts or disconnections.

6) Testing before use

Thoroughly test the setup with a multimeter to ensure correct voltage and current at the outputs before connecting to the final load. It's important to simulate actual load conditions during testing to check the real-world performance of the configuration.

7) Monitoring and maintenance

Regularly check the performance of the setup and look for signs of stress like excessive heat, noise, or voltage drops. Periodic checks will help catch issues before they lead to failure.

1) List All Components

Start by listing all industrial devices that will be powered by the supply. This includes motors, sensors, PLCs (Programmable Logic Controllers), fans, lighting, and any other electrical or electronic equipment.

2) Determine Individual Power Requirements

Obtain the power consumption ratings for each component from their datasheets or product labels. These are usually given in watts (W) or can be calculated from current (amperes) and voltage (volts) if wattage is not directly provided.

3) Sum Up Total Power Consumption

Add together the wattage of all listed components to get the total power requirement. This sum represents the minimum power your supply should be able to provide.

4) Include a Safety Buffer

Add a 20-30% buffer to the total power requirement. This buffer accounts for potential inefficiencies, variations in power demand during peak loads, or future additions to the system. This extra capacity helps ensure that the power supply will not be operating at its maximum limit continuously, which can extend its lifespan and provide more reliable performance.

5) Consider Peak vs. Continuous Load

Differentiate between peak power requirements and continuous operation power requirements. Some industrial equipment, like motors, may have a higher startup power (peak power) than their running power (continuous power). Ensure the power supply can handle both.

6) Adjust for Power Factor and Efficiency

Check the power factor (PF) and efficiency of the power supply. These factors affect the actual power available to the devices. For instance, if a power supply has an efficiency of 80% and a power factor of 0.9, it will need to draw more power from the mains to deliver the same amount of usable power to the load.

7) Final Calculation

Incorporate all these factors to finalize the required wattage of the power supply. This final figure should guide the selection of a power supply that meets all operational demands of your industrial setup.

Modular power supplies allow you to connect only the cables you need, reducing clutter and improving airflow within the chassis. This flexibility is beneficial for custom builds and maintenance, as you can easily add or remove cables.

Non-modular power supplies have all cables permanently attached, which can lead to excess wiring if not all connectors are used, but typically cost less than modular models.

When selecting a power supply, look for certifications that indicate compliance with international safety and performance standards. Key certifications include UL (Underwriters Laboratories), which ensures safety for the U.S. market; CE (Conformité Européenne), which is mandatory for products sold in the European Economic Area; and FCC (Federal Communications Commission), which governs electromagnetic interference in the U.S.

These certifications guarantee that the power supply meets rigorous health, safety and environmental protection standards.