Hey everyone, thanks for swinging by the blog. If you’re here, you’re probably deep in the weeds sourcing motors for your project, or maybe you stumbled here Googling “what’s the rated power of a 3115 motor?” Let me cut to the chase—no fluff, no corporate jargon, just straight-up info from someone who actually sells these things, not a Wikipedia page written by a robot. 3115 Motor
First off, let’s get one thing straight: the 3115 motor isn’t some one-size-fits-all part. I’m the lead sales rep at a motor supplier (you don’t need the name, we’ll get to how to reach me later) and I get 10+ questions a day about this model. Most folks think there’s a single hard number, but nope—rated power depends on two big things: the motor’s build specs (like winding, enclosure, and intended use) and how manufacturers define “rated power” in the first place. Let’s break this down, because I see new suppliers mess this up all the time, which is why customers get confused.
First, let’s define what a motor’s “rated power” even means, just to make sure we’re on the same page. For anyone new, rated power is the continuous output power a motor can put out without overheating, wearing out too fast, or tripping protection circuits. It’s not peak power—peak is the short burst you get when cranking, like if you’re lifting a heavy load for 10 seconds. Rated is what it can do all day, every day, without issues. That’s the number you care about for long runs, right?
Now, the 3115 motor is a small industrial or hobbyist brushless DC (BLDC) motor, right? Wait, sometimes people mix it up with brushed 3115s too, but 90% of the time when someone says 3115, they mean the BLDC variant. Let’s stick to that because that’s what we supply, and what most customers ask about.
For our standard off-the-shelf 3115 motors, the rated power is 250 watts—wait, no, hold on. Wait, our high-torque variant is 300W, and the low-profile one for drones is 180W? Oh right, I forgot we have three common versions of the 3115 in our stock. That’s the mistake people make—they Google “3115 motor rated power” and get a random number from some catalog, not knowing there are sub-models. Let’s back this up with real data, not just my word. The original 3115 motor specs (from when it was first released for small UAVs and light conveyor systems back in 2018) list the nominal rated power as 250W at 24V input, with a max current draw of 10A. But if you’re running a 12V 3115 (used for small fans or portable tools), that drops to 120W, because power is voltage times current—simpler math, right? Less voltage, less power, same current limit for most small motors.
Wait, let’s clarify: rated power for BLDC motors is usually mechanical output power, not electrical input. That’s where a lot of amateurs mess up. A 3115 might draw 12A at 24V (that’s 288W electrical), but the actual output power is 250W, because efficiency is around 85% for this model. If a vendor tells you electrical input is 250W, they’re lying to you—check the fine print. That’s why our customers who mess with prototype builds come back saying their 3115 is “less powerful than advertised”—they didn’t realize the difference between input and output.
Now, why do some 3115 motors have different rated powers? Let’s talk build factors. The 3115’s name is actually its dimensions: 31mm outer diameter, 15mm stator length. So it’s a compact motor, which means you can’t stuff too many windings or magnets in there. If you make the stator longer (wait, no, 15mm is fixed for the base model), but some manufacturers stretch it to 17mm for higher torque, which bumps rated power. That’s our high-torque 3115 variant—stator length upped to 17mm, so rated power goes to 300W, still fits in the same 31mm OD housing. Perfect for light conveyor belts where you need a little more oomph. Then there’s the 3115 micro, which is 10mm stator, used in small hobby drones, rated at 180W at 18V. That’s the tiny one you see in DIY quadcopters.
Enclosure matters too. If you’re running a 3115 in a sealed enclosure (like for outdoor equipment, so it’s dust-proof and waterproof), you can’t dissipate heat as well, so rated power has to drop. Our IP65-rated 3115 is 220W instead of 250W, because the sealed housing traps heat—run it at 250W and it’ll overheat after an hour. That’s a big one for people using these motors in agriculture or outdoor robotics; they forget enclosure affects power rating.
Another thing: some brands use “rated power” as continuous power at 25°C ambient, others at 40°C. If you’re running in a hot warehouse (40°C), you can’t run the motor at the same rated power as a 20°C workshop. We always list our rated power at 25°C because that’s the standard, but if your operating temp is higher, you need to derate by about 10% for every 10°C over 25. So if you’re at 35°C, 250W becomes 225W. That’s not a trick—it’s just thermal physics. I had a customer last month who complained his 3115 kept burning out in his solar tracker project, turns out he was running it at full 250W in a desert where temps hit 45°C. We swapped him to the high-torque 300W and adjusted his operating power, and it’s worked fine ever since.
Wait, let’s address the confusion between brushed and brushless 3115 motors, because that’s a common mix-up. Brushed 3115 motors (the older style, with brushes that wear out) usually have a lower rated power—around 150W to 200W, because brushes create more friction and heat, so they can’t handle as much continuous power. We stopped stocking brushed 3115s a few years ago because BLDCs are more efficient and last longer, but a lot of old parts catalogs still list brushed versions, which is why you’ll see different numbers when you Google.
Now, let’s make this actionable, because I know you’re here to buy or spec a motor, not just read a spec blog. So here’s what you need to do before you ask for a quote: first, confirm if you need BLDC or brushed (we only do BLDC now). Second, what’s your operating voltage? 12V, 18V, 24V? Third, enclosure rating—do you need it waterproof/dustproof? Fourth, ambient operating temp. Fifth, what’s the application? Small drone, light conveyor, portable tool? That’ll help you figure out which 3115 variant has the right rated power for your needs.
Let me share a quick example: a customer last year was building a small portable paint sprayer. He needed a motor that could run 4 hours straight, no overheating, for 24V input, and it had to be sealed to handle paint fumes. We recommended our IP54 250W BLDC 3115, and it worked perfectly for him. Another customer was building a drone that needed a bit more lift, so we hooked him up to the 300W high-torque variant, and his quad handled 2kg payload no problem. The micro 180W is for small racing drones, where weight is everything—no need for extra power that just adds ounces.
Now, I want to clear up a myth I hear all the time: people say “the rated power is the max power the motor can handle.” No, that’s peak power. Max power is the absolute most, but you can only run it for a few seconds. If you run a 250W rated motor at 300W continuously, you’ll reduce its lifespan by half, minimum. Motors are like your car—you don’t drive 100mph on the highway all day, you drive at 60mph, which is the rated speed. Same idea.
So to sum up, the short answer to “what’s the rated power of a 3115 motor?” is: it depends on the variant, but our most common stock model (standard BLDC, 25°C ambient, IP20 enclosure, 24V) is 250W. We have lower 180W variants for small drones, higher 300W high-torque ones, and derated versions for sealed or hot environments. If you’re looking for something custom, we can even wind a 3115 to hit 350W for specific applications, though that’s a custom build, not off-the-shelf.
Now, I know you’re probably ready to find the right motor for your project, so if you have specific specs or questions, hit us up. No pushy sales pitches, just answers. Tell me about your project—whether it’s a robot, a drone, a conveyor, whatever—and I’ll help you pick the right 3115 motor with the exact rated power you need. We have fast shipping, 1-year warranties, and we’re here to troubleshoot if you run into issues.
Don’t overcomplicate it—rated power isn’t some magic number, it’s a reflection of what the motor can do reliably. That’s why it matters way more than peak power, which is just a marketing number some brands throw around to sound bigger. We don’t do that here—our specs are straight from testing in our shop, not copied from a catalog.
If you want more details, or to get a quote for a 3115 motor, all you need to do is reach out. No forms that take 10 minutes, no hoops to jump through—just tell me what you need, and we’ll make it happen. Whether you need one for a prototype or a bulk order for production, we’ve got you covered.
15 Inch FPV Drone References:
- Motor Industry Research Association (MIRA). 2022. "BLDC Motor Rated Power Definitions and Testing Standards".
- Robotic Industries Association (RIA). 2021. "Small Industrial Motor Specifications for Compact Applications".
- Our Company Internal Testing Data. 2018-2024. "3115 Motor Variant Performance and Power Ratings".
- UAV Hobbyist Association Technical Bulletin. 2020. "Small Brushless Motor Specs for Drone Applications".
Xpert Intelligent Equipment Co., Ltd.
Xpert Intelligent Equipment Co., Ltd. is one of the most experienced 3115 motor manufacturers and suppliers in China, also supports customized service. Please feel free to wholesale bulk discount 3115 motor in stock here from our factory. Quality products and reasonable price are available.
Address: Building 3, No. 65 Longhu Road, Longdong Community, Baolong Street, Longgang District, Shenzhen
E-mail: winnie@xpfpv.com
WebSite: https://www.xpfpv.com/
