+ Post New Thread
Results 1 to 20 of 20
  1. #1
    Member level 2
    Points: 353, Level: 4

    Join Date
    Aug 2018
    Posts
    46
    Helped
    0 / 0
    Points
    353
    Level
    4

    Using 0-10V analog sensor output with rasbery pi

    Dear all.
    I am new bie to rasberry coding and ckt design. I have 4 analog sensor which gives 0-10v DC output and 4-20mA current. I am looking for ckt that can read these range of Current and voltage parameter with 12bit/16bit resolution.

    Some people using
    https://ncd.io/raspberry-pi-0-10v-analog-output-module/https://store.ncd.io/product/1-chann...rter-i%C2%B2c/
    https://store.ncd.io/product/mcp3428...c-mini-module/

    https://shop.controleverything.com/p...controller-i2c

    Is there any schmatic avilable for it

    •   AltAdvertisement

        
       

  2. #2
    Super Moderator
    Points: 76,257, Level: 67
    Achievements:
    7 years registered
    Awards:
    Most Frequent Poster 3rd Helpful Member

    Join Date
    Apr 2014
    Posts
    15,468
    Helped
    3517 / 3517
    Points
    76,257
    Level
    67

    Re: Using 0-10V analog sensor output with rasbery pi

    Hi,

    It depends on what your input is.
    Most properly an ADC....with what decodable analog input voltage range?

    For 0..10V just use a resistive voltage divider.
    For 4..20mA use a resistor.

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



  3. #3
    Member level 2
    Points: 353, Level: 4

    Join Date
    Aug 2018
    Posts
    46
    Helped
    0 / 0
    Points
    353
    Level
    4

    Re: Using 0-10V analog sensor output with rasbery pi

    using voltage divider network we can reduce the range , Is there any proven schematic with 12/16 bit resolution using MCP module



  4. #4
    Super Moderator
    Points: 76,257, Level: 67
    Achievements:
    7 years registered
    Awards:
    Most Frequent Poster 3rd Helpful Member

    Join Date
    Apr 2014
    Posts
    15,468
    Helped
    3517 / 3517
    Points
    76,257
    Level
    67

    Re: Using 0-10V analog sensor output with rasbery pi

    Hi,

    What's wrong with just two resistors? Too simple?

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



  5. #5
    Member level 2
    Points: 353, Level: 4

    Join Date
    Aug 2018
    Posts
    46
    Helped
    0 / 0
    Points
    353
    Level
    4

    Re: Using 0-10V analog sensor output with rasbery pi

    i need good resolution . my question is how can i do it.



  6. #6
    Advanced Member level 2
    Points: 2,948, Level: 12
    baileychic's Avatar
    Join Date
    Aug 2017
    Posts
    588
    Helped
    49 / 49
    Points
    2,948
    Level
    12

    Re: Using 0-10V analog sensor output with rasbery pi

    10V/4095 = 0.00244V
    3.3V/4095 = 805.86uV

    If Pi is used for ADC reading then you need to scale the 10V to 3.3V.

    10V - 3.3V = 6.7V

    6.8k and 3.3k will do.

    What resolution you want from scaled 3.3V? nano volt, pico volt?



  7. #7
    Advanced Member level 1
    Points: 2,659, Level: 12

    Join Date
    Aug 2016
    Posts
    470
    Helped
    72 / 72
    Points
    2,659
    Level
    12

    Re: Using 0-10V analog sensor output with rasbery pi

    Hi,

    I think the information given about the sensor is not very clear. We have 0-10V and 4-20mA. Is there any relationship between the two? That is to say, does the voltage change with change in the current?

    - - - Updated - - -

    Please give more info.about the sensor.
    -------------
    --Akanimo.



  8. #8
    Super Moderator
    Points: 76,257, Level: 67
    Achievements:
    7 years registered
    Awards:
    Most Frequent Poster 3rd Helpful Member

    Join Date
    Apr 2014
    Posts
    15,468
    Helped
    3517 / 3517
    Points
    76,257
    Level
    67

    Re: Using 0-10V analog sensor output with rasbery pi

    Hi,

    Resolution has nothing to do with resistors.
    Just choose the correct resistor ratio.

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



    •   AltAdvertisement

        
       

  9. #9
    Member level 2
    Points: 353, Level: 4

    Join Date
    Aug 2018
    Posts
    46
    Helped
    0 / 0
    Points
    353
    Level
    4

    Re: Using 0-10V analog sensor output with rasbery pi

    Click image for larger version. 

Name:	MCP3424.png 
Views:	8 
Size:	47.9 KB 
ID:	153626

    I have schematic for reference . If i wanted to use 0-10V dc reading of analog voltage

    Channel-1+ & channel - should be given in range of 0-5V through voltage divider network

    vout=(Vs*R2)(R1+R2) -> R1=R2=1K Vs=0-10V from DC output/sensor

    If it is 0-30V dc
    vout=(Vs*R2)(R1+R2) -> R1=5K R2=10K Vs=0-30V from DC output/sensor

    Is it correct ??



    •   AltAdvertisement

        
       

  10. #10
    Super Moderator
    Points: 76,257, Level: 67
    Achievements:
    7 years registered
    Awards:
    Most Frequent Poster 3rd Helpful Member

    Join Date
    Apr 2014
    Posts
    15,468
    Helped
    3517 / 3517
    Points
    76,257
    Level
    67

    Re: Using 0-10V analog sensor output with rasbery pi

    Hi,

    0..10V is correct

    0...30V is wrong.
    See it this way:
    30V should become 5V.
    This is 6:1 ratio.
    Voltages behave like the resistance values.
    Thus you need 6 "parts" in total where 1 "part" is the output.
    --> So "one part" at the lower end and 5 parts at the upper end.

    Klaus

    Btw: there are more than enough descriptions for this in the internet, even online calculators and explaining videos. Just do an internet search.
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



  11. #11
    Advanced Member level 2
    Points: 2,948, Level: 12
    baileychic's Avatar
    Join Date
    Aug 2017
    Posts
    588
    Helped
    49 / 49
    Points
    2,948
    Level
    12

    Re: Using 0-10V analog sensor output with rasbery pi

    Upper resistor 27k
    Lower resistor 3.3k

    ADC connected across 3.3k.



  12. #12
    Advanced Member level 4
    Points: 6,247, Level: 18
    kripacharya's Avatar
    Join Date
    Dec 2012
    Location
    New Delhi
    Posts
    1,209
    Helped
    182 / 182
    Points
    6,247
    Level
    18

    Re: Using 0-10V analog sensor output with rasbery pi

    Isn't it just FUN trying to teach a newbie about ohm's law.. where he is already working with mircocontrollers and what not without a clue ?
    Its just sickening.

    you make a 'sketch' (copied of course), and "bootload it" .. no clue what that means. And a cute little led starts blinking.
    brilliant. idiotic.



  13. #13
    Advanced Member level 2
    Points: 5,009, Level: 16
    Achievements:
    7 years registered
    ZASto's Avatar
    Join Date
    Jan 2008
    Location
    Messy Corner, 44°47'31.56"N, 20°28'9.16"E
    Posts
    593
    Helped
    119 / 119
    Points
    5,009
    Level
    16

    Re: Using 0-10V analog sensor output with rasbery pi

    These "new kids on the block" should first learn the basics of electrotechnic, to understand what is Voltage, Current, Power, Resistance, Capacitance, Inductance, and to UNDERSTAND howa Transistor works.
    Without transistors there would be no microcontrollers, microprocessors, ...

    Unfortunately, arduino is for such kids that are not willing/able to switch the brain ON, just c/p some sketches.
    Make no mistake between my personality and my attitude.
    My personality is who I am.
    My attitude depends on who you are.



  14. #14
    Super Moderator
    Points: 29,548, Level: 41
    andre_teprom's Avatar
    Join Date
    Nov 2006
    Location
    Brazil
    Posts
    8,816
    Helped
    1114 / 1114
    Points
    29,548
    Level
    41
    Blog Entries
    9

    Re: Using 0-10V analog sensor output with rasbery pi

    The simple mention of 4-20mA sensors suggests the action of remote measurement, which by itself would be a strong argument for using galvanic isolation, such as analogue optical couplers. Unfortunately many questions here are posed not contextualized, and probably only throughout the replies is that needed information will arise, by increments.
    --------------------------------------------------------------------------------------------------
    Part of the world that you live in, You are the part that you're giving ( Renaissance )



  15. #15
    Full Member level 6
    Points: 4,254, Level: 15

    Join Date
    Nov 2005
    Location
    Norway
    Posts
    344
    Helped
    75 / 75
    Points
    4,254
    Level
    15

    Re: Using 0-10V analog sensor output with rasbery pi

    0 - 10V and 0(4)-20mA is normal industrial interfaces.
    One thing about 4 - 20mA is that many sensors transmit error levels in the 0-4mA range and some also above the 20mA level (22-23mA).

    To make a proper interface you should take this into account, and check out the sensors you want to use in the application.



  16. #16
    Advanced Member level 1
    Points: 2,659, Level: 12

    Join Date
    Aug 2016
    Posts
    470
    Helped
    72 / 72
    Points
    2,659
    Level
    12

    Re: Using 0-10V analog sensor output with rasbery pi

    The OP needs to give more info than there is now.

    If a sensor is giving 4-20mA then you can convert it to a 1-5V signal by passing it across a 250-ohm precision resistor. An ADC can then work on this.
    -------------
    --Akanimo.



    •   AltAdvertisement

        
       

  17. #17
    Advanced Member level 1
    Points: 2,659, Level: 12

    Join Date
    Aug 2016
    Posts
    470
    Helped
    72 / 72
    Points
    2,659
    Level
    12

    Re: Using 0-10V analog sensor output with rasbery pi

    I think we have to differentiate between sensor and transmitter here.
    -------------
    --Akanimo.



  18. #18
    Advanced Member level 4
    Points: 6,247, Level: 18
    kripacharya's Avatar
    Join Date
    Dec 2012
    Location
    New Delhi
    Posts
    1,209
    Helped
    182 / 182
    Points
    6,247
    Level
    18

    Re: Using 0-10V analog sensor output with rasbery pi

    Quote Originally Posted by Akanimo View Post
    The OP needs to give more info than there is now.

    If a sensor is giving 4-20mA then you can convert it to a 1-5V signal by passing it across a 250-ohm precision resistor. An ADC can then work on this.
    I always thought a 4-20 loop was meant for digital signalling in noisy long (I.e. high impedance) loops. This would be converted to voltage of choice at receiver by use of a suitable R, which was not necessarily 'precise'.

    What have I missed ??



  19. #19
    Advanced Member level 1
    Points: 2,659, Level: 12

    Join Date
    Aug 2016
    Posts
    470
    Helped
    72 / 72
    Points
    2,659
    Level
    12

    Re: Using 0-10V analog sensor output with rasbery pi

    Quote Originally Posted by kripacharya View Post
    ...digital signalling...

    What have I missed ??
    I think that's what you've missed.
    -------------
    --Akanimo.



  20. #20
    Advanced Member level 4
    Points: 6,247, Level: 18
    kripacharya's Avatar
    Join Date
    Dec 2012
    Location
    New Delhi
    Posts
    1,209
    Helped
    182 / 182
    Points
    6,247
    Level
    18

    Re: Using 0-10V analog sensor output with rasbery pi

    Quote Originally Posted by Akanimo View Post
    I think that's what you've missed.
    No, that's what I was pointing out. It's digital, so what need for an ADC ??

    - - - Updated - - -

    Oh wait ... haha. My mistake. It IS analog.



--[[ ]]--