Hi,
I am using a sensor like the one here
Which i purchaed from ebay
(https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F273282662081)
The listing says that the output should be VCC, in my case 12v. I am reading 2v.
May I ask if the sensor in the robot shop listing behaves the same and what the purpose of the accompanying board is? I have seen the skematic for the board and am not sure what it does.
I would also like to know what the 4th black M/signal wire is for.
Many thanks in advance for any help.
Regards?
Peter
Hello @Hackmagic and welcome to the forum!
May I ask if the sensor in the robot shop listing behaves the same and what the purpose of the accompanying board is? I have seen the skematic for the board and am not sure what it does.
Yes, both use the same chip so they behave the same way. The accompanying board is an interface adapter that makes it compatible with DFRobot “Gravity” interface.
The listing says that the output should be VCC, in my case 12v. I am reading 2v.
If the liquid level sensor detects the presence of liquid, it will output HIGH but If no liquid is detected it will output LOW. (Output voltage (high level) : VCC / Output voltage (low level) : 0V)
You can find more information about this sensor here:
https://wiki.dfrobot.com/Non-contact_Liquid_Level_Sensor_XKC-Y25-T12V_SKU__SEN0204
Let us know if it helps!
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Hi geraldinebc15,
Thank you for the reply. From the schematic the sensor can be cycled through the sensitivity settings by pulsing pin 4 to gnd. I assume when power is disconnected and reconnected the sensitivity will be reset. Is my understanding correct?
Would you have any idea why the output would be 2v when the input VCC is 12v? I expected it to be 12v also.
Regards,
Peter
Hello again,
The working principle of the sensor is to use the water sensing capacitor to detect whether the liquid is present. In the absence of liquid near the sensor, there will be a presence of distributed capacitance, and therefore there is some certain static capacitance to ground on the sensor. When the liquid level slowly increases close to the sensor, the parasitic capacitance of the liquid will be coupled to the static capacitance so that the final capacitance value of the sensor becomes larger and the changed capacitance signal is then input to the control IC for signal conversion. Then converting the changed capacitance into the amount of change in the electrical signal. Lastly, by using a certain algorithm to detect and judge the degree of this change we can determine when the amount of change exceeds a certain threshold that means the liquid level to reach the induction point.
why the output would be 2v when the input VCC is 12v?
I imagine you mean when the water level reaches the sensor, right? In this case, I imagine the sensitivity must be set to low.
BTW I thought I should mention this since the page where you bought the sensor doesn’t (or at least I didn’t see it), you shouldn’t use a metallic container (you can use plastic, ceramics, etc) and if you do use one, you have to do this:
