UPS backup for your printer

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If the printer is being used in an area where the power grid has issues constantly, you might wish to install a UPS (Uninterruptible Power Supply) with the printer. UPS can compensate for power surges, voltage fluctuations, and temporary power loss.

Some considerations need to be made when purchasing the UPS.

Power panic (selected models only)

The Original Prusa MK4/S, MK3.9/S, MK3.5/S, MK3/S/+, and XL printers are equipped with a Power Panic feature, which recovers the print when the energy is back after a power outage. If power outages are constant, make sure to test the Power panic.

The power panic will work over multiple power outages, even if the printer is not re-started.

Choosing a UPS for your printer

If using a UPS is necessary, it is recommended to use a UPS that uses Line interactive technology. A Standby UPS will cause the printer to restart due to the higher triggering time.

A UPS is chosen based on the apparent power (VA) needed for the system. It is not recommended to use UPS smaller than 1000 VA for the printer.

Note that a UPS will not run your printer for a long amount of time. If a power outage lasts a long time, it is recommended to safely turn off the printer and start the print again after the power is back. For the printers with no Power Panic, the print will have to be started from the beginning.

How long will the UPS power my printer?

We have tested each printer using a Line interactive 1500 VA UPS. See below the information from each printer.