ESC Passthrough


I am working on my mapping quadcopter. For my 4 to 6S supporting motor, I was using hobbywing ESCs. Now I have got a little lighter ESC. However, it says BLHELI_S. So far, I have gone through the document of ESC passthrough as well as information about this BLHELI_S ESC that I have got. The ESC description says, it supports 3 to 6S and is for 300-size racing drones. The description regarding the passthrough doesn’t say when and who needs to use the passthrough feature. or I would say, I have missed it out to read somewhere.
Q1 - Can’t I use this ESC for mapping drones?
Q2 - The ESCs are working fine (operating motors), but the flight is not done, should I go with passthrough?

I have also purchased a BLHELI 32 4 in 1 ESC for the same quad and the same application. This is T-motor Velox. I have not done any wiring or testing so far.
Q3 - Will this need a passthrough or will it work out of the box?
Q4 - Will both the racing-based ESCs work with the quad for mapping or is it not for slow and stable flying?

Requesting you to guide me through this.

Thank you.

Pass-Through is simply this (Wiki description is as good as any):
The Pass-Through feature allows BLHeli32 and BLHeli_S ESCs to be upgraded and configured using the corresponding BLHeliSuite32 or BLHeliSuite application (running on the user’s PC) while the ESCs remain connected to the autopilot.

I would install the T-Motor 4in1 ESC. BLHeli_32 offers more than _S. Assuming they support the current requirement they will work with any type craft. Depending on your Motor kV you might have to disable Low RPM Power Protect via BLHeli Suite. As stated above Pass-through can be used for that.

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Thanks, Dave for your input.
So, does that mean, it won’t work out of the box as we wish it to work/perform? or do they fly fast (like a racing drone) out of the box?

Yes. 4 in 1 and separate, both ESCs have the capacity to give out the required current. No issue in that way.

Thank you

You should define the ESC firmware type you are using in the parameters.
There’s also an additional check box if you are using T-motor ESCs.
If you’re changing hardware configuration, I suggest saving a .param file so you can ‘restore’ previous settings.
As Dave said, the pass-through feature is meant to allow communication between a computer and the ESC through the flight controller.

Your Q2 is not clear, can you fly, or not? Have you gone through the tuning processes?

Thanks for giving the idea of saving the .param file for future restoration.
ESC firmware type defining in passthrough or Mission planner?

Basically, if I define it simply, I want to use 1 set (4 nos.) of BL Heli ESC with by motor. I have connected with the motor and PDB and FCB. ESC calibration is also done. It is operating fine without propellers. I was just wondering whether it will fly well or not, out of the box (without any passthrough). That is why asked whether passthrough is mandatory or not.

So, Q2. was, I have done all the ground setup and ground operation testing is also done. Just away from the flying field. (not done with the tuning process)

And these questions occurred as the ESC is for racing. So wondering if it will automatically fly fast or what? Because I am not into racing drones.

Also, as you mentioned above Dave’s explanation, I agree, is needed for communication between ESC and PC through FCB. The thing I was thinking is, “it is required when I need to change certain parameters. Otherwise not required and should work directly out of the box.”
Your input and guidance will help better.

It’s more accurate to say they are “marketed” for racing. They will perform fine under broad application.

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