After some calibration, thanks to some friends of this forum, I found that the problems I had (power loss and even stop motors during a flight) are due to a ESC overheating. It reaches 140 C in about three minutes and the ESC starts its safety procedures. I touched the ESC and of course is very very hot. I don’t exactly know if is possible that with this configuration (current is about 35-40A) is normal to reach that temperature. Is it maybe because a defective ESC or hardware configuration (the ESC does not have a lot of airflow and need to be placed in another place) or is just parameter configuration?
In the next photo you can see the location of the ESC:
ESCS are usually rated with high airflow, so you will either need to go for a much larger rated esc, it will have lower resistance so less heat generated or you need to add airflow, either a small fan or a duct to get air over the esc.
But I think that the info you show is just for one motor, and I’m using 4 motors which is much more than enough. I did my calculations with eCalc. And currently I’am able to hover at 17% thrust with a total current consumption of about 40A. So, I don’t think the problem comes from here, but I am not really sure.
Regarding the props, I’m using the biggest ones that fit in the drone size. I need this reduced size because of the task that the copter have to do.
Okey, that’s a thing I didn’t know at the time to pick the ESC. I calculated that 45A per channel would be enough, in fact, to hover I just need about 10A per motor. But of course, if the ESC was designed to have a lot of overflow this is not for me…
Do you think that maybe individual ESCs should be a better option in this case? Or that maybe I can place the ESC in a better place?
Yes info is for single motor. What prop size are you using? For 4in1 esc you should make good air flow or thinks can go wrong like in your case. Try lower your Esc so heatsink have enough room to spread heat.
The props are AzurePower Race Propeller 6145 Tri-blade . Yes, I moved the ESC but I wrongly think that leaving more space in the bottom part would be a good idea, wrong…
Definetely I will try to leave the maximum space I can in the upper part.
I was suggesting to leave more space on top, on the top of Esc are heatsink and temparature by nature are going up. You can also add a small fan on top of heatsink to lower temps, but that is going to make some other (problems) if fan is too much vibrating. Do you have good quality wires going from Esc to Motors? Low quality wires have greater resistance and also can increase a Esc tempararure.
Yes I understood, I moved the ESC in a position a bit more forward (not just in the middle of the panels) and leave some extra upper space, as you can see in the image.
Now the temps seems to be a bit more controlled and stabilize at 120C. But I’m not sure if this temperature is still too much high.
The wires are Turnigy 18 AWG, and I think that are good enough because the ones connected to the motors are just 20AWG.
I’m am thinking in moving the ESC full outside of the structure ant vertically attached. Do you think is a good idea?
I think Esc is more then covered with airflow now. Im not sure what else can you do now other then add fan or change esc to one with more Amps. Pretty sure that motors pull’s alot of current. Do you have calibrated current monitor properly so you can be sure about Amp draw?
If you ran eCalc as you said you must have seen the warning about max current over the limit for that ESC. As @geofrancis suggested earlier you should have selected a higher rated 4-in-1. 120C is cooking pretty good, that may degrade the ESC quickly.
Yes I’m pretty sure because, now that I can fly a full battery, the flight time is the expected with that consume. According to Matek I should configure BATT_AMP_PERVLT to 66.7 but of course with this value the current showed was excessive (about 65 - 70 A hovering) which does not make any sense. A full battery flight would be 7min and I flew 12min this morning.
Maybe the solution would be to buy a ESC with more Amps supported.
Yes of course I saw, but the intention is just to fly very very relaxed. So with this in mind and seeing the hover consumption in eCalc, we thought that 45A per motor would be more than enough…
I will try to change the ESC position again to see if better results in temp are reached. If not, we should buy a better ESC or maybe individual ESCs.
In your case individual ESC’s may be the better choice. Not as clean looking but practical.
If you can find suitable ones that is. These days the selection is a bit limited. I see DYS has some AM32 units that look interesting but I have never used their products.
One question, in the case the motor is located oriented down (like we have the front motors), so the individual ESC would be situated in the arm being above the motor and the props, the airflow would be sufficient?
