# VOXL ESC calibration + T-Motor F2203.5 3550KV Source: https://forum.modalai.com/topic/1557/voxl-esc-calibration-t-motor-f2203-5-3550kv Category: ESCs, Sensors and Accessories (https://forum.modalai.com/category/15/escs-sensors-and-accessories) Tags: esc Posted: 2022-11-21 18:57:44 UTC by mbahrami Replies: 5 · Views: 1900 ## mbahrami · 2022-11-21 18:57:44 UTC Hello, I'm using [VOXL ESC Tools](https://docs.modalai.com/modal-esc-v2-manual/#voxl-esc-tools) to calibrate VOXL 4-in-1 ESC v2 on a cutom-built airframe (~7") with T-Motor F2203.5 **3550 KV** and [propellers](https://www.modalai.com/collections/accessories/products/seeker-propellers) 6" x 4". 3S and 4S batteries were used to power the ESC passed through a VOXL Power Module v3. without props being installed (no load), the motors spin normally in response to ``voxl-esc-calibrate.py" [video](https://drive.google.com/file/d/1W6stXt7ETKKb2Lidz3-WL0cN8X2-ET3t/view?usp=sharing) ![Screenshot from 2022-11-18 14-23-40.png](https://forum.modalai.com/assets/uploads/files/1669056510092-screenshot-from-2022-11-18-14-23-40.png) but with props, the motors spin abnormally and can not pass the initial phase. ``voxl-esc-calibrate.py" sends out 0 RPM as though the motors are not spinning. [video2](https://drive.google.com/file/d/1Dm36HVX-Vf4uD4Cw_hHcyuTCP6N_pmqx/view?usp=sharing) ![Screenshot from 2022-11-18 14-24-36.png](https://forum.modalai.com/assets/uploads/files/1669056613295-screenshot-from-2022-11-18-14-24-36.png) - the idle amp of the ESC was measured at 0.46 Amp. - max power was limited on purpose here. Is there any consideration for the setup or recommendation on [VOXL ESC Tools](https://docs.modalai.com/modal-esc-v2-manual/#voxl-esc-tools) to calibrate other than using new motors with a lower Kv to get a higher torque? thanks ## Reply by Alex Kushleyev (ModalAI staff) · 2022-11-22 02:32:00 UTC Hi I can look into it. Can you please share the ESC params that you are trying to use while calibrating? ## Reply by mbahrami · 2022-11-22 15:58:08 UTC thanks for the replay. The ESC params I used for the results I shared above are [Seeker_V1_tmotor_f2203_1500kv_Param_Rev_A](https://gitlab.com/voxl-public/flight-core-px4/voxl-esc/-/blob/master/params/Seeker_V1/Seeker_V1_tmotor_f2203_1500kv_Param_Rev_A.xml). I also tried with [esc_params_modalai_4_in_1_revb_1400KV_TMotor_MN1806](https://gitlab.com/voxl-public/flight-core-px4/voxl-esc/-/blob/master/params/old/esc_params_modalai_4_in_1_revb_1400KV_TMotor_MN1806.xml) and [Starling_V1_emax1306B_2700kv_4030_3S_param_Rev_A](https://gitlab.com/voxl-public/flight-core-px4/voxl-esc/-/blob/master/params/Starling_V1/Starling_V1_emax1306B_2700kv_4030_3S_param_Rev_A.xml) and a few more which had a Kv coefficient more than 2000. But the results are the same as I have shared. That said, today I used [esc_params_modalai_4_in_1_revb_holybro2216_880](https://gitlab.com/voxl-public/flight-core-px4/voxl-esc/-/blob/master/params/old/esc_params_modalai_4_in_1_revb_holybro2216_880.xml) which has Kv=800 and a [4S battery](https://www.modalai.com/products/4s-battery-pack-gens-ace-3300mah), and this setting worked for calibration. I tried with a 3S battery but it could not provide enough power. After ~%30 PWM commanded, the RPM drops (picture attached). I wonder if there are any of these [ESC params](https://gitlab.com/voxl-public/flight-core-px4/voxl-esc/-/tree/master/params) which I can use with a 3S battery as well. PS.1. I tried with changing "vbat_nominal_mv" in the ESC params xml files but that did not work. PS.2. I have a [VOXL Flight Deck](https://www.modalai.com/products/voxl-flight-deck-r1?variant=31790279196723) on the drone. ![wierd.png](https://forum.modalai.com/assets/uploads/files/1669132586408-wierd.png) ## Reply by Alex Kushleyev (ModalAI staff) · 2022-11-22 16:39:11 UTC Hi @mbahrami , I just tested a similar motor Tmotor 2203.5 2850Kv with a 6 inch propeller at 12V power supply, using the Seeker V1 params and the motor starts and runs fine. I also tested other param files and every time it is able to start fine. Based on the behavior and observed RPM vs PWM result, i believe that either the Motor or the ESC is faulty. So I suggest the following: - test the same motor on another ESC channel (same ESC) - test a different motor of the same type on the same ESC, same ESC channel Note that due to 3-phase nature of the motor, it is possible for motor to spin with only two phases fully working and spinning without load is easier for a faulty motor / ESC. This will help figure out which one of the two (motor or ESC) is faulty. My guess would be that the ESC is the issue, but you will see. I hope this helps! ## Reply by mbahrami · 2022-11-22 17:43:36 UTC yes @Alex-Kushleyev, having done the test, it seems the ESC is faulty. I should have mentioned this before, but in my tests only the motor on the ESC's ID/channel 3 was working and the rest on the channels/IDs 0, 1, 2 were not work. so just used T-motor 2203.5 **3550 Kv** with the Seeker V1 params and the VOXL Wall Power Supply (12V) and switched the motors on different ESC IDs/channels. Again the new motor on the ESC id=3 was working and the others not. I also changed the motors and the same results using the Seeker V1 params. by the way the soldering did not seem to be an issue because I have checked them out by continuity tests. ![IMG_3615.jpg](https://forum.modalai.com/assets/uploads/files/1669138261651-img_3615-resized.jpg) ## Reply by Chad Sweet (ModalAI staff) · 2022-11-22 18:32:17 UTC Please follow the steps here at https://www.modalai.com/pages/rma