Bench test with T500 and T200


I am using 2 T200 and 1 T500 thruster. I am connecting them to the battery via a customized zero board. My question is that I want to do endurance test with all the three thrusters at the same time. I am using Pixhawk to give PWM signals to the thrusters. I want to practically test all three thrusters at the same time using QGroundControl. How will I implement the same. Thank you .
Gofloat Tech