Jump to content
Sign in to follow this  

how to test for BP20..??

Recommended Posts


There is information on testing all of our sensors in the Knowlegebase section of the NRG Systems website:


Here is what it says about BP-20:

Testing a BP-20 pressure sensor

Tools Required:

  • 7 V DC to 35 V DC source (12 V nominal, battery recommended)
  • Digital Voltmeter (DVM) set to 20 V DC scale




  • Disconnect BP-20 from logger
  • Connect DC supply (-) to black wire
  • Connect DC supply (+) to red wire
  • Set DVM to 20 V DC scale
  • Connect DVM (-) to black wire
  • Connect DVM (+) to white wire (Note: older units have a both a green wire and white wire.  In this case, use the green wire.)
  • Measure and record output voltage on white wire (typically near 4 Volts)...
  • To determine the absolute pressure as reported by the BP-20 use the following:


kPa = (21.79 x Vout) + 10.55


Perfomance Comparison:

  • Check this value against the logger display to confirm scale is correct.

  • Check this value against another barometer to confirm reading is correct.

  • Note: BP-20 should draw about 8 mA of current



  • BP-20 voltage output is measured to be 4.123 V DC...
  • kPa = (21.79 X 4.123) + 10.55
  • kPa = 100.4

Share this post

Link to post
Share on other sites

 Yes thanks Dave, but i dont know how many voltage it is die? output voltage beetwen black wire and white wire of me (BP-20) is ~ 10V

what happen with it (BP-20) ? it die or good? thanks Dave so much. i waiting answer of you!

Share this post

Link to post
Share on other sites


Does the voltage change, or remain constant?

10 V corresponds to a barometric pressure reading of 228 kPa. This is not a realistic reading for anywhere on the surface of Earth.

Check to be sure the weep holes on either side of the cable strain relief are not plugged; they should be free for air to flow in and out. You can check this with a pin or paper clip.

If the weep holes are clear and the sensor maintains unreasonably high pressure readings, it may be that the sensor is damaged.

Share this post

Link to post
Share on other sites

Join the conversation

You are posting as a guest. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Create New...