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Pressure sensor (Bar30) and (Bar02) weird behavior

Hello,
I have two pressure sensors (Bar02 and Bar30).
I have used both sensors and they were working fine but after a while (two weeks on average) when I open the serial monitor I get “starting” and then no readings at all as if it’s stuck or something.
The I2C bus is working fine, another sensors was on the bus and was functioning. I checked the wiring and I everything.
What causes the sensor to malfunction?

Hi @ASmarine,

This isn’t an issue I’ve heard of before.

A couple of questions here:

  1. Is this two weeks of continuous measuring, or are you saying they were working each time you turned them on within a two week period, and then stopped working afterwards? If it’s continuous measurement note that both the Bar30 and Bar02 are not intended for extended submersion, and should be dried fully once per day (as specified on the relevant product pages and on the sensor datasheets).
  2. Given you’ve mentioned a serial monitor I assume you’re using an Arduino or similar. If your board runs on and communicates with 5V, are you using an I2C level converter to drop the communications to 3.3V for the sensors? This is mentioned in the Bar02 Arduino Guide, and covered in depth in the Bar30 Arduino Guide.

If neither of those is the issue then I’d suggest adding some extra Serial.println calls in the script that you’re running, to help determine where it’s getting up to.

No continuous operation.
Just a period of 2-3 hours every three days on average. The vehicle is normally placed in a very sunny place so it dries out very quickly.

I guess it’s the I2C voltage level that caused the sensors to malfunction. I’ve been using an I2C converter for a while but it was lost. I had to act quickly so I wired the Arduino directly to the sensor (I often do that with raspberry pi (also I2C 3.3 v level) without issues). It worked fine for a relatively long time which led me to believe it was okay.

Good thing I posted this so that buyers get to know what issues could arise from such acts.

I will try to use another voltage level converter and see if the damage is permanent. Just to keep thread followers updated.

Ahh yeah, that can definitely cause premature failures (as with any case of operating something outside its specification). Unfortunately it’s not always an immediate bang/smoke, which can give a false sense of security until the relevant component fails much sooner than expected.

Raspberry Pi and Bar30/Bar02 both use 3.3V I2C, so they should be directly compatible, whereas most Arduino boards use 5V, which is where a level converter becomes necessary.

If it stopped working when it previously was working I would guess that the damage is likely to be permanent, but it at least doesn’t hurt to try :slight_smile: