The two main decisions to make when choosing a power supply are the voltage and total power required. In general, 24V is recommended and a power supply that is rated for at least 20% more than is required provides some headroom.
Minimum and maxium input voltages for Duet boards.
Minimum input voltage | Max input voltage | |
---|---|---|
Duet 3 Mainboard 6HC | 11V | 48V (v1.02 and later), 32V (v1.01 and earlier) |
Duet 3 Mainboard 6XD | 11V | 30V |
Deut 3 Mini 5+ | 11V | 25V |
Duet 3 Expansion 3HC | 12V | 48V (v1.02 and later), 32V (v1.01 and earlier) |
Duet 3 Expansion 1XD | 12V | 48V |
Duet 3 Expansion 1HCL | 12V | 50V |
Duet 3 Toolboard 1LC | 12V | 32V |
Duet 2 WiFi/Ethernet | 11V | 25V |
Duet 2 Maestro | 11V | 25V |
Usually, 12V or 24V is used because other components (heaters, fans etc.) are readily available at these voltages. There are three factors that may make 24V preferable to 12V:
The Duet 2 Maestro uses TMC2224 drivers, which work best with lower current motors (hence higher inductance) motors. For this reason, we recommend you use 24V power with the Duet 2 Maestro, especially if the printer is a delta. If you use 12V power, the maximum travel speeds you can achieve may be lower.
These can be purchased from MeanWell resellers. The usual electronic component distributors sell similar power supplies.
This is typically the best option if you are comfortable with wiring the mains voltage terminals and with the price. These power supplies are invariably CE-approved and typically include power factor correction. They are available in 12V and 24V versions with a wide range of power ratings. They usually include a voltage adjustment potentiometer.
These are similar to the MeanWell supplies but are made to lower quality standards. They are available very cheaply from eBay suppliers. They usually claim to be CE-compliant, but take this with a pinch of salt because some of them use leaded solder. They include voltage adjustment potentiometers.
Expect these to be less reliable than MeanWell and similar quality PSUs. On the other hand, they may also give years of service, and if they do fail they are cheap to replace. If you choose one of these then it is recommended that you get one with at least 20% more power capacity than you expect to need.
Here's an example of what may happen when they fail. The output inductor was clearly under-rated for this application. The PCB below was badly burned.
Widely available from eBay, Amazon etc. and from PC parts sellers. You can get cheap no-name ATX power supplies, and also ones from a respectable brand such as Corsair.
Advantages compared to the other types listed above:
Disadvantages:
The power rating of an ATX supply is based on a combined load on the 12V, 5V, and 3.3V outputs. So you need to ensure that the 12V output alone is capable of supplying the entire power requirement of your printer.