What Does Daisy Chaining Mean for Power Supplies?

PBUS-45-PULS-DaisyChaining-400.jpg

November 21, 2022

By Maximilian Hülsebusch, Global Product Marketing & Communications Manager, PULS Power

The colloquial term daisy chaining has established itself as a description for the direct connection of technical devices in series. In this blog article, you will learn what you should consider if you want to operate several power supplies in a daisy chain.

Daisy chaining refers to a wiring scheme in which several devices, such as power supplies, are connected directly in series. This type of wiring is also referred to as “looping through”. The English term “Daisy Chaining” is used colloquially, since the structure is vaguely reminiscent of a daisy chain. The principle can be used both to achieve a higher total current and to transmit analog signals or digital data.

If the wiring of a power supply system is planned according to this principle, it is not wired in a star configuration. Instead, the current is looped through to the load in a linear or ring-shaped manner on one line.

Is daisy chaining recommended for power supplies?

Before setting up a power supply system using the daisy chain method, it is essential to check the data sheet for the relevant type of power supply. Some power supplies do not allow direct connection of outputs. If this warning is ignored, there is a safety risk. It can lead to overloaded circuits and even fire hazard.

Daisy chaining with 240W power supplies (CP10.241)

If a power supply is suitable for daisy chaining the outputs, particular attention must be paid to the specification of the connection terminals. The decisive factor here is the load on the terminals: The maximum specified current of the terminal must not be exceeded, even with the last power supply in the series. PULS specifies the corresponding current values in the product data sheets. For example, a maximum current of 25A is permissible for the 240W power supply CP10.241 (24V, 10A). (See graphic 1) If more than three power supplies are connected in parallel, a fuse or circuit breaker must be integrated for each power supply output. Alternatively, a diode or a redundancy module can be used. This protective measure increases the safety of the parallel connection.

Incidentally, devices with output terminals, which feature two positive poles and three negative poles, are best suited for daisy chaining. Most PULS power supplies are equipped with these terminals as standard.

As you can see, daisy chaining should only be used with caution on power supplies and by qualified staff. But what if this method is not allowed for the selected power supply according to the data sheet? Or, if it is theoretically allowed, but the required current should be higher than the specified current which is allowed for the connection terminals?

What is the alternative to daisy chaining?

A reliable alternative to daisy chaining is the usage of distribution terminals in the control cabinet. In this case, the outputs of the power supplies and the input of the load are connected to the distribution terminals. (See graphic 2) The total current is thus no longer limited by the maximum current allowed for the power supply terminals and can be higher.

Solution with distribution terminals as an alternative to daisy chaining.

Conclusion

Daisy chaining of power supplies is a common practice in industrial applications. To increase the total current, the outputs of several power supplies as well as the load can be connected directly to each other. The decisive factor here is the information on the maximum permissible current that may flow through the connection terminals of the power supply units. These values can be found in the respective data sheet. However, not all power supplies are suitable or approved for daisy chaining. Therefore, this wiring method should always be carried out only by qualified staff on the basis of the data sheet information.

Important_Links_Bar.jpg

https://products.pulspower.com/us/blog/post/what-does-daisy-chaining-mean-for-power-supplies

Related Articles

Network Infrastructure Featured Product Spotlight

PBUS 14 Panduit logo 400

This webinar presented by Beth Lessard and Keith Cordero will be highlighting three Panduit solutions that will optimize network equipment and cabling to ensure that your spaces are efficiently and properly managed to support ever-evolving business needs of today and beyond. Products that will be featured include PanZone TrueEdge Wall Mount Enclsoure, Cable Managers, and Adjustable Depth 4-Post Rack.

REGISTER HERE


Editor’s Pick: Featured Product News

Siemens: SIMOVAC Non-Arc-Resistant and SIMOVAC-AR Arc-Resistant Motor Controllers

The Siemens SIMOVAC medium-voltage non-arc-resistant and SIMOVAC-AR arc-resistant controllers have a modular design incorporating up to two 12SVC400 (400 A) controllers, housed in a freestanding sheet steel enclosure. Each controller is UL 347 class E2, equipped with three current-limiting fuses, a non-load-break isolating switch, and a fixed-mounted vacuum contactor (plug-in type optional for 12SVC400). The enclosure is designed for front access, allowing the equipment to be located with the rear of the equipment close to a non-combustible wall.

Read More


Sponsored Content
Explore the Benefits of Industrial Control Panel Certification

The growth of industrial machinery and automation is driving a growing need for industrial control panels (ICPs) globally. The UL 508A Industrial Control Panel Shop Program is part of UL’s General Coverage Program, which offers control panel manufacturers flexibility in applying UL Certification Marks to a wide range of industrial control panel designs. Our Industrial Control Panel Program covers multiple requirements like proper component usage, enclosure environmental ratings, wiring and motor protection, safety markings, and conformance to the National Electric Code® (NEC) and Canadian Electrical Code (CEC).

Learn more HERE.


Products for Panel Builders

  • Banner Engineering: S15J In-Line Fuses

    Banner Engineering: S15J In-Line Fuses

    This addition to Banner Engineering’s series of plug-and-play connections delivers quick and easy overcurrent protection anywhere it’s needed in a circuit. The rugged housing allows for use in harsh environments with other series components, and the visual feedback system provides quick status updates at a glance. No matter where a device is in a circuit, an S15J fuse can be installed quickly using the simple 5-pin M12 connection. A compact 15mm diameter barrel allows placement in areas where space is a concern. Read More…

  • BK Precision: 9200B Series Multi-Range Power Supplies

    BK Precision: 9200B Series Multi-Range Power Supplies

    Any 9200B series model can replace several supplies on your bench or in your rack. Unlike conventional supplies with fixed output ratings, these multi-range power supplies automatically recalculate voltage and current limits for each setting, providing full output power in any Volt/Amp combination within the rated voltage and current limits. For benchtop applications, these power supplies provide a numerical keypad for direct data entry along with convenient cursors and analog style knobs to quickly make incremental voltage or current changes. Read More…