TroubleshootingArduino

Set up a pressure transducer with HW-685 current to voltage converter

userHead Brian.Shaw 2025-12-29 19:43:41 75 Views1 Replies

It may not be appropriate for me to post this topic here since the hardware that I need help with was not purchased here. Furthermore, although I selected Arduino as a tag, one of the components of my application is actually a Particle Photon (not an available tag), but that discrepancy should have no bearing on the issue I am confronting. Assuming it's OK to continue, here is a description of my application and the problem I am having getting it to work:

 

I have a new pressure transducer that is designed to measure water levels up to 1 meter. When it is connected to an HW-685 current to voltage converter, I do not get valid readings of water level. 

 

At the start of my setup process I connected a 4-20 mA signal generator to the voltage converter and successfuly calibrated the latter. Custom firmware running on an attached Particle Photon accurately reports that the water level increases from 0 inches to about 40 as I increase the current from 4 to 20 mA. That verifies that the converter and the firmware are all working precisely as intended.

 

But when I connect the sensor the level is reported to be 40 (+/-) inches even though the sensor isn't under water; obviously I expected it to read 0. I subsequently discovered that if I completely disconnect the sensor, the reported value remains unchanged! Put another way, the presence or complete absense of a sensor has no bearing whatsoever on the readings. Just for the hell of it, when the sensor was connected, I put it in about a foot of water but no change at all. 

 

The wiring is precisely as shown here except the power for the converter is coming from the VUSB pin on the Photon, not the 12 volt power supply:

 

https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/313/KIT0139_Web.pdf?_gl=1*9lpqz2*_up*MQ..*_gs*MQ..&gclid=Cj0KCQjwrojHBhDdARIsAJdEJ_elZ6LYAN6BIaTbzaDau3BU7QjSBnvo4vXHRwDJ5WqiGVO29fIpkKIaAokKEALw_wcB&gclsrc=aw.ds&gbraid=0AAAAADrbLlgVsWs06G75yCw3VEhjFwWWZ

 

Note that I just received a second sensor - one that i designed to measure up to 5 meters of water - and connecting it in place of the other one does not change behavior in any way.

 

Here is a photo of the test environment:

The sensor is connected on the left side of the photo. Note that while the signal generator is in the photo, it is not currently connected to anything but power.

 

Can anyone here help me figure out why this is not working?

2026-01-06 19:13:22

I'M Rosley Rodrigues Are you aware that you could be scammed while trying to invest into crypto? If you know this then you will have to do a thorough search before investing your funds into any platform. Crypto Recovery Scam: Desperation has been the major key used by scammers to get into victims, CRYPTO RECOVERY is real but not legal. What is real and not legal has procedures and one can likely fall into imposter hands and end up being scammed, so many reviews about crypto recovery have been posted by scammers who derive joy in seeing their fellow humans in tears. I will solemnly advise everyone to stop searching for crypto recovery agent in a wrong way, they are now so many search words on the internet being used by both real and fake, so therefor a new methods was introduced to connect with a real recovery agent which i myself writing this article has experience it magnificent excellent recovery work well done by SMITH WHITE HACK SERVICE crypto recovery/other’s General hack service. SMITH WHITE HACK SERVICE and his team are a great set of hackers team with verified profiles and they have been helpful in resolving scam issues simply with their technology tools and p2p forum union with crypto block, makes it much easier for them to carry out crypto scam funds recovery. My total scammed funds was $4.875,000 canadian dollar’s and I received $3.255 USD, converting that to Canadian dollar’s was greatly profitable and I had no regret for clearing out all the scammer wallet funds with the help of.
( [email protected] )
 

userHeadPic Rosley