Pixhawk 4 ESC wiring

#1

I’m building a quad’. Frame: tarot 650 ironman.
The motors are sunnysky 380kv.
ESCs: hobbywing xrotor 40amps.(which has got 2 signal wires with a servo connector.


Question is… How should I connect the ESC signal wired to the Pm07 power management board?
And just to clarify, can the ESCs get their signal from the FMU PWM-OUT?

#2

I almost made this same mistake of trying to connect the ESCs to the FMU-PWM-out. For a mulirotor setup at least, you don’t use those pins. You’re going to have to cut the plastic connector off of the braided signal and ground wire. Then if you look at the Power Management Board (PMB), you will see the small holes that say M1, M2, M3… that are located near the GND pads. That is where you solder the ESC Signal wires. The black wire that wraps around the signal wire is just there to protect the signal wire from interference. You should just be able to solder that to the GND pad along with the larger ground power cable coming from the ESC.

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#3

Thanks a lot. This has been of great help.
Now I’m having another problem, Q Ground Control cannot detect any radio channels on my drone… It was detecting the radio channels and all seemed well. I then changed my ground station to mission planner and flashed ardupilot firmware to it and also detected the radio channels… Now, I had connected all my ESC signal cables to the receiver channels.
Mission planner couldn’t also perform the motor test. I get the error “command was denied by the autopilot”
When I tried to takeoff, of course with much difficulty from the radio, the quadcopter attempted to lift, one side must have generated more lift and it toppled upside down. One of the motors and it’s ESC seemed affected as there was smoke from the both of them (motor and its ESC).They also felt very hot. The motors seemed to try to rotate even when the vehicle was upside down and the transmitter was off. So I disconnected the vehicles battery. When I later tried to connect the vehicle to the mission planner, radio channels were not being detected. I switched back to using Q Ground Control as my ground station, flashed firmware back to px4 and it couldn’t also detect the radio channels…
The motor that smoked seemed to be unaffected
The following is my hardware:
Autopilot: pixhawk 4,
Power: pixhawk 4 PM07 power management board.
Motors: Sunnysky x4108s 380kv
ESCs: hobbywing xrotor 40amps
Radio: Radiolink AT10 II transmitter, Radiolink R12DS receiver, Radiolink PRM-01 battery voltage telemetry sensor.

What could be wrong?
Why aren’t my radio channels being detected by the ground station?
Why couldn’t mission planner perform the motor test?

#4

Wow glad I found this post. I’m about to start soldering and was unsure. It seems johns route is the preferred option? Any update from anyone before I plug that iron in?? Many thanks

#5

Glad to see this post too. I also thought I should plug the ESCs’ servo plugs into the power management pins. Never thought about clipping off the plug and soldering them. I wish there was a “plug-in” option to make the connections a bit less permanent in case ESC’s needed changed. Wouldn’t have to de-solder things.

#6

I used the FMU rail for my quad because I’m too lazy to solder them again and again as I try different setups. If you plug the cable into the I/O PWM-Out on the Pixhawk and into the FMU-PWM-in on the power distribution board, you can plug the ESC’s into the corresponding pins on the FMU-PWM-out rail and it works fine. At least mine does.

#7

Thank you Occularmagic. I appreciate the recommendation. I’ve been waffling over which Flight Controller to buy. It looks like it will probably be the Pixhawk 4. I’ve looked over the DJI stuff, TopXGun and a few others, but they don’t have the features I am looking for.

In case you are interested, my bird is a 1050mm class Y-6 configuration with Tarot 5008, 340KV motors, 18" props. I’m planning to use a Sony A6000 camera and gimble that I scavenged from a crashed work Trimble drone. I mostly fly drones at work for aerial mapping over construction sites. I need to be able to flight plan to have automatic camera triggering for the mapping. I had hoped to build this drone to do similar type work and also for aerial photography.

Thanks again

#8

Occularmagic…incidentally, when I look at the Pixhawk 4 through Holybro’s site, it comes with your choice of a plastic case or an aluminum one (at a different price ofcourse). Do you know of any real advantage one way or the other… besides a probably weight difference?

#9

I have tried all different types of controllers, and honestly, I haven’t found one that does absolutely everything I’ve wanted to do in one package, but the Pixhawk seems to be the closest at the right price for me. I’m not sure how much experience you have with configuring everything required but it was a bit daunting for me. I don’t fly them for work, but I do love to experiment with different setups and have learned a lot through that. If you’re looking to setup something for aerial mapping and photography, you’ll for sure learn a lot. I haven’t set up an A6000 on a remote trigger before so don’t know how easy/hard it will be. There’s a lot of good info out there, but some of it will be just different enough from your setup that it won’t work like it should. Then you’ll have to figure out why. That’s part of the fun for me though. As far as plastic vs aluminum, I don’t know the weight difference, but with a 1050mm Y6, I don’t think plastic vs aluminum will change your flight time or agility much. And I can’t think of any physical reason why one would be better, other than corrosion resistance? No idea. More importantly, have fun no matter what you get! Ha ha!