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AC DC Converter to Drone

I am wondering if I can solder a female xt60 connector to this AC to DC power converter and then plug into my Kakute F7 Mini stack? The Tekko32 esc says up to 45 amps and this ac to dc converter says it delivers 12V DC Power Supply 8.34 Amp.

Does anyone with power knowledge know if this solution is safe to test? I want to be able to plug this in at my desk without having to always worry about keeping a charged battery around. I believe the 12V DC is safe since the esc takes 3-6s. But the 8.34amp is where I get lost.

I have done this in the past on a 3amp supply, The tekko32 esc can handle a maximum amperage of 45amps that it draws from the battery when the motors are heavily loaded. But if the motors are just sitting on the desk and not turning then the amp draw is low because all you are driving are the electronics within the esc. You will see a blip when the ESCs arm but it is low. Just make sure you don’t run the motors beyond the limit of your bench top power supply, as the ESCs have power the props should be removed.

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Thank you!

“Just make sure you don’t run the motors beyond the limit of your bench top power supply”

I will be testing code that runs the motors (thanks I’ll make sure I remove props). Would you mind walking me through what your quote means above? I am attaching a screenshot of my motors specs. If I run my motors at 99% and this power supply only puts out 8.34 amp – won’t the motors only get 8.34 amp? I’m wondering if this hurts any of the hardware or it just doesn’t spin the motors as fast as they could go if the power supply was say a 25 amp? Thank you for your time

If the bench top power supply is protected from overload then the motors/esc will only receive 8.34amps. If not then you could damage your power supply. I don’t know what the motors/esc amp draw would be without props, it’s also not a good idea to run motors flat out.

That is really helpful, thank you very much

Sorry – if you have a spare minute I was thinking about your response… I’m wondering if it is always good form to use a power supply that can handle the max of the hardware using it, in this way you don’t have to worry about damaging the drone or power supply?

In this scenario if I had a 12V 50 amp power supply the esc would pull as much as it needed and since it never goes near 50 amp it wouldn’t damage the power supply and the power supply in turn couldnt harm the esc because it only serves the amps requested by the esc? Thank you again

Yes, it is always better to have a power supply that delivers the correct voltage and more than the required maximum current. This protects the power supply.
But powerful power supplies are expensive.

Another solution is to use a “current-limited, constant-voltage power supply”. These intelligent power supplies deliver a (user definable) constant voltage as long as the electrical current output is under an user defined electrical current value (in Ampere).
I use one of these, limiting the current at around 3 Amps. This allows the copter to run, but as soon as I arm the motors, the electrical current will try to go over 3 Amps, and the power supply will drop the voltage in such a way as to limit the current to be smaller or equal than the predefined 3Amps. The result is that the voltage drops so much that the copter reboots. That is perfect and exactly want I want.
The advantage is that such power supplies (5A to 10A) are really cheap when compared to a proper 50A power supply.

Interesting! Ill start digging in to this. I am so grateful thank you!!

Something like this: https://www.amazon.com/LW-K3010D-Adjustable-Switching-Regulated-Spectrophotometer/dp/B07512KQDW/ref=sr_1_22?dchild=1&keywords=AC-DC+current+limited+constant-voltage&qid=1599939920&sr=8-22

or if you already have a bench power supply: https://www.amazon.com/LW-K3010D-Adjustable-Switching-Regulated-Spectrophotometer/dp/B07512KQDW/ref=sr_1_22?dchild=1&keywords=AC-DC+current+limited+constant-voltage&qid=1599939920&sr=8-22

Just ordered it, thank you!!

Side question if you are still there… If my motors say they pull 27a but my esc says max output is 45a, I only need to worry about my motors at this point correct? That is my power wont go to 45a will it since the motors max draw is 27a? Again, thanks so much

Yeap, that is correct. but sometimes datasheets are not accurate

I am in your debt. Thank you for your help!

Hi,
I’m an electrician / technician by trade.
I am using an adjustable power supply (0-30V & 0-50A) for any drone testing (non flight) and software updates.
In flight I have 3 cell battery. So when using power supply I set it to 12V and usually limit current to about 5A. In this way I can up- and download data from controller and other things without having to remove props because if I was accidentally arming drone then the limit of current wouldn’t allow the motors to spin. But it also allows me to calibrate current sensor of drone by cranking up the amps to something like 30A and then running motors at low speed whilst drone is secured to ground.
…just a handy trick to know.

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Very interesting thank you Karl!

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