It can happen to anyone. You’re 14 hours into a 15 hour print, only to lose all progress from a random power outage. If this has ever happened to you, you know how frustrating it can be. Thankfully, there are some things you can do to prevent you from losing all progress due to a power outage.
So how can you protect your 3D printer from power outages? You can hook it up to an uninterruptible power supply, or UPS, which is basically a battery backup. You could also upgrade to 3D printer that has a power loss detection function, which allows it to save its position where it lost power and continue from that point when power is restored. If neither of those options appeal to you, there are some do-it-yourself solutions.
I’ll go over each of these options in depth in this article.
Uninterruptible Power Supplies
An Uninterruptible power supply, or UPS for short, is basically a battery that will immediately kick in if the power goes out. This will prevent devices from shutting down as soon as they lose power. In the case of a 3D printer, it can mean the difference between being able to pause the print and continue it later, or losing many hours of progress in an instant. With a powerful enough UPS, a printer could probably even continue printing for an hour or more, potentially completing the print before the power comes back on.
The good thing about a UPS is that it is extremely easy to install. You simply plug your 3D printer into the UPS and then plug the UPS into an electric outlet. The outlet simultaneously powers the printer and charges the battery of the UPS until it’s full.
The amount of time that a UPS can power your printer depends on the model, and generally the more money you spend on it the more powerful it will be. They range in price from around 45 USD to well over 1,000 USD, but those super high end models are designed more for running servers, not 3D printers. Even the cheapest UPS should give you at least a few minutes to pause the print and save the coordinates so that you can resume it later from that point.
As for what UPS to buy, there are a few things to consider. First you need to determine your printer’s power consumption. It should say in the owner’s manual the amount of power your printer draws, usually in watts. If you’re like me and lost the manual, you can use what’s called a Watt meter or power meter to determine your printer’s power use. These are relatively cheap and you just plug them in line with your printer and it can tell you the wattage, voltage, and kilowatt hours that your device uses.
Once you have determined how much power your printer uses, you’ll want to choose a UPS with a wattage rating that is at least 50 to 75 percent higher than that amount. UPS are all rated in volt amps, but many also tell you the amount of watts that they can handle. This shouldn’t be a problem as even the 45 dollar UPS has a rating of 425 volt amps or 255 watts, which will far exceed the needs of most small printers, which is usually around 40 to 50 watts. If you want to plug in multiple devices to your UPS and not just your 3D printer, like for instance your computer and monitor, then you’ll want a UPS that exceeds the total combined watt usage of all of those devices.
As for what brand to go with, there are a few to consider.
- On the lower end there is the CyberPower Systems model CP425SLG, which has a power capacity of 255 Watts, which could definitely handle one 3D printer. This UPS only costs around 45 USD and has a run time of up to 2 minutes at full load, but if you only use it for your 3D printer then it will probably last longer. It probably won’t be enough to keep the printer running for an hour, but that’s not really the point. A UPS like this is perfect to give you just some extra time to pause your print so that you can resume it later.
- On the higher end, there is something like the APC Back-UPS Pro UPS, which comes in volt amp ratings of 1000 to 1,500. Depending on the model it ranges from $135 to $165 USD, which might seem like a lot, but this UPS can handle much higher loads than cheaper models and will keep them running for longer. If you’re looking for a UPS for more than just your 3D printer, you might want to consider something like this.
Printers with Power Loss Detection
To save you from worrying about battery backups, some printers come with functions that detect power loss and will automatically save the location where it stopped so that it can continue later once power is restored. Surprisingly, even many high end printers don’t come with a power loss resume function. I hope that as the technology advances more manufacturers make it a standard feature because it is very useful. After my research I could only find two printers that come from the factory with power loss detection and resume functions already installed.
- The Prusa I3 Mk3S is one of the best 3D printers on the market for its features and quality. It has a rigid, high quality extruded aluminum frame, and really all of its parts are of good quality. The motors are fast and quiet, and it has software features that help with the quality of prints. For instance it can detect skipped steps or if any layers have shifted. And yes, it can detect when power has been lost and will save and shutdown so that you can continue once the power has been restored. As of the day this article is written, the Prusa I3 Mk3S sells for $749 USD as a kit, or $999 USD fully assembled.
- The Creality3D CR-10 Mini is quite a bit cheaper than the Prusa I3 Mk3S, and it comes with the ability to resume prints after power loss, so it’s a good option if you’re looking for a cheaper 3D printer. As of right now this printer sells for around $300 USD, so it’s significantly cheaper than the Prusa even if you buy the kit version, but don’t expect the same quality of parts in the CR-10 Mini as the Prusa I3 Mk3S. Still, for the price you get a good sized 3D printer with that very important power loss recovery feature.
I’m not sure why so many other 3D printers don’t come standard with this feature like the two printers mentioned above, especially when it’s so important, and already available even in a $300 printer.
DIY Fixes
If you’ve already bought a 3D printer that doesn’t have any sort of power loss resume capabilities, and you don’t yet have a UPS, then there are still some ways that you can resume a print even after your printer has shut down and forgotten where it stopped. There are actually many ways to do it, and they all depend on what software your printer and slicer uses, but they have certain steps in common.
Basically what you can do is either count the layers, or determine the exact Z axis height that your print stopped at by manually adjusting the height and finding where it almost touches your failed print. Then you can edit your g code from your slicer by removing all the previous layers, and make sure that it starts at the height that it stopped at before. If you do that properly, and it might take a few tries before you get it to work, then it should resume printing exactly or pretty close to where it left off. How exactly you go about doing this will depend on what slicer you use, and also the software that your 3D printer uses, and I don’t have experience with every type out there so you’ll have to search how to edit the g code for the specific kind that you have.
Conclusion
It’s almost inevitable that your printer will fail at some point, either from a power outage, stuck filament, or somebody accidentally shutting it off. If you don’t have measures in place to protect it from those situations, then you can only hope that it won’t happen near the end of a very long print. As the saying goes, “An ounce of prevention is worth a pound of cure,” so in my opinion it’s best to go with a UPS or get a printer that can save itself from those things. It’s much easier than trying to fix it afterwards.