This is probably something basic, but I havn't found any similar problems out there.
I have been using the MG-811 CO2 sensor from Sandbox ( MG-811 CO2 Gas Sensor Module | Sandbox Electronics ) for a few months, with good results. Recently, I've wanted to add modularity to the project by making the sensor easily removable, so I addded a DIN plug. Glitch!
Here's what I've tried (all on the same Arduino Mega MCU):
-connect MG-811 (VCC,GND,VOUT,HeatingVCC,HeatingGND) via DIN -> doesn't work
-equal length wire, without the DIN -> works fine
-connecting a new, different DIN plug -> doesn't work
-other sensors using the same DIN plug (K30 NDIR CO2 sensor and SEN0148 Humidity sensor) -> works fine
-connect MG-811 to other heating power source, disconnect DIN-routed heating power -> doesn't work
--is there something basic that I don't know about DIN plugs? any help would be greatly appreciated--
The shell should only be used for shielding not current, use another pin
Boardburner2:
The shell should only be used for shielding not current, use another pin
Shot, thanks, I originally wasn't using the shield for anything, then I tied the ground of the 12v switching power supply to it, just to see what happens.
Also, what specifically does shielding refer to?
Shielding is to prevent interference from outside signals , if your din cable is carrying audio for instance it can pick up mains hum , these days there are many other problems due to digital stuff like computers.
My suspicion is that you have the pin ordering wrong.
Use tails and use a multimeter to test continuity through each cable.
pofadder:
-connect MG-811 (VCC,GND,VOUT,HeatingVCC,HeatingGND) via DIN -> doesn't work
Thats 5 connections by my count.
Your pic shows four plus shell.
The din cable if a purchased one may only have a connection to the shell at one end.
Boardburner2:
Shielding is to prevent interference from outside signals , if your din cable is carrying audio for instance it can pick up mains hum , these days there are many other problems due to digital stuff like computers.
My suspicion is that you have the pin ordering wrong.
Use tails and use a multimeter to test continuity through each cable.
Thanks! Good to know.
I don't currently have a multimeter, but I did disconnect the wires one by one from the DIN and then directly connect them to the Mega to troubleshoot pin order problems. The only configuration in which the sensor data does make sense is when the VOut line does not run through the DIN (storebought, btw).
I'm going to get a multimeter and figure out what's going on the lines
Thats 5 connections by my count.
Your pic shows four plus shell.
The din cable if a purchased one may only have a connection to the shell at one end.
Sorry, the picture's not that clear, but there are six pins and the shield (you can see the red, black, green, blue, yellow and white wires connected. the sixth connection is the boolean pin that I'm not currently using).
Thanks for the help so far!
Cheers
P
