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Voltage & current & 5.3V power supply 200A

Dear Ladies and gentleman,

i got a problem with the in the Topic mentioned power module. I`m using an PixHawk 2.1 with the PX4 firmware and i get wrong current readings from the sensor with the parameters from the Productpage (Voltage readings are fine)

My current parameters are :
Voltage offset 0,4V
Amp/V 37,4
Voltage divider 7,65

I`m using a 6s 30Ah Lipo battery. the measured ccurrent from my system in standby (Battery pluged in and Autopilot running / no motors) is at 0,7A measured with a power meter. Seonsor value is at around 14A

Advice needed for this problem.

Measured the voltage from the sensor myself and calculated the parameter. Working fine now but the value is miles away from the specified value.

Hello,

What value have you found please?

The value i found is 90.38 A/V for the 200A Module

My value for the Amp is also fare from the suggested value.
Are the value provided on https://drotek.gitbook.io/pixhawk-3-pro/main-devices/power-supply/tiny-module
are supposed to be exact?

I’m getting 7.85 for the voltage divider and about 2.5 for A/V

Hello,
Here is the link for the ACS758 datasheet
https://www.allegromicro.com/~/media/Files/Datasheets/ACS758-Datasheet.ashx

From the datasheet the sensitivity of the ACS758ECB-200B is 10.0 mV/A @ 20 °C.
Wouldn’t make the Amps per volt setting: 100 A/V? Is the ACS Viout directly connected to the board I out?

Also do you have the datasheet for the voltage sensor?

At the moment the following values seems to get ok results:
Voltage offset 0,37V
Amp/V 80 A/V
Voltage divider 7,85

As a reference, I’ve performed test of my 5 power bricks and it seems that setting the Voltage offset is very important.

My values for are within the following range:
Voltage offset 0,36-0.41V
Amp/V 75-95 A/V
Voltage divider 7,60-7.90

@Paul_T,
I was interested to know if the power brick is tolerate to reverse voltage? I’m asking as I’m looking to integrate a ESC with regenerative braking.

Thanks