How To Choose a DIN Rail Power Supply?

DIN rail power supplies have become the standard for reliable and efficient power supplies. They are an integral part of many applications such as mechanical engineering, industrial automation, logistics, automotive industry, wind power, process industry and many more.

What is a DIN rail power supply?

A DIN rail power supply is a switched-mode power supply that converts unstabilised input voltage into regulated output voltage. Switched-mode power supplies are characterised by their significantly higher efficiency and lower weight as well as a more compact design than linearly regulated power supplies (transformers).

The special feature of DIN rail power supply is their type of mounting, to which they owe their name. The power supplies are attached to the standardised DIN rail, which is also known as a top hat rail.

The DIN rail is a mounting rail made of metal with fixed standard dimensions. These dimensions were originally defined by the German Institute for Standardization (DIN). This type of mounting has been established worldwide and adopted into a European (EN) and international (IEC) standard.

The term top hat rail (TS 35) comes from its U-shaped or hat-shaped profile.

The DIN rail is found in most industrial applications around the world. It has become a fixed component of cabinets, distribution boxes and machines. The selection of available electrical components (power supplies, circuit breakers, relays, industrial PCs, etc.) for this type of mounting is almost unlimited.

What should I consider when choosing a DIN rail power supply?

This is the first piece of basic information you should know.

Do you need a power supply for a one-phase or three-phase system? Does the power supply also need to be able to operate at the input DC voltage?

What voltage and current do you need at the output?

Do you want to use the power supply as a single unit or in parallel? Not every DIN-rail power supply automatically has parallel functionality.

The second criterion concerns the environment in which the DIN-Rail power supply will be used.

What are the average and maximum ambient temperatures? Please note that most power supplies require derating above a certain temperature and no longer have full power.

Is the application located in a high humidity, dusty or vibrating environment? It is then recommended to consider using a DIN-rail power supply with a conformal coating on the PC board.

Knowing the correct dimensions will make it easier for you to choose the right power supply.

How much space is available for DIN rail power supplies?

Can you also mount the power supply in a vertical standard alignment? If the power supply can only be mounted horizontally, airflow will be compromised and a derated installation may be required.

The power supply units need to be placed a certain distance to the left and right to allow air to circulate and for the units to remain as cool as possible. When planning the cabinet, please consider the distances specified in the instruction manuals and data sheets.

Can the power supply be mounted on a DIN rail or does it have to be connected to the cabinet?WODE offers suitable solutions for alternative installations