Hi all,
I’m trying to use the Adafruit SHT30 ADA5064 to replace a dead Temp/Humidity module in my weather station which uses an SHT30 chip. The station uses a board marked WHP0120C1V01, with no additional components on it. The Adafruit board has a number of SMD resistors marked as 103 but measuring open, and a diode on the +ve supply which I have bypassed. There’s also a cap which I’ve left alone. I have confirmed the Address pins on both modules are tied to the Gnd pins. The SDA, SCL and Gnd pins on the Adafruit module all measure as connected directly to relevant the SHT30 pins, so I don;t know what the components are meant to do and as far as I can tell the unit should fire up OK as I’ve made sure the 4 wire connections are correct.
I’ve confirmed there is 3.5v getting to the modeule form teh weather station. (it’s a “Fine Offset” HP1003, pretty much the modern replacement for the original Jaycar model, fitted with a supercap in addition to the solar panel and rechargeable alkaline batteries). Others with this unit have reported success with the SHT30 Digital Temperature and Humidity Sensor Module 2.4-5.5V GY-SHT30-D Module from EBay, and I have a few of these on order.
Any ideas on what to try next wouldbe welcome
Hi Brian,
Could you please send through a few photos of your setup? Just in case there is something small we can spot it’s always worth having a second set of eyes look over the wiring and it may save quite a headache if there is something minor and hard to spot.
Since both modules use the SHT30 we’ve got a good shot of getting this working, the catch will be working out what each manufacturer has done differently in their implementation of that sensor module.
Double-checking the expected I2C address and confirming the I2C pullup resistors are equivalent values would be the next big step to verify why I2C communication isn’t happening yet.
The resistors labelled 103 measuring open should be measuring at most 10,000 Ohms, so that’s a cause for concern.
Since posting, I looked agaain at the Weather Station forum and noted they had to reset the station - I’ve just done that and it looks like I’m now getting readings!! - the temperature is off by about 6 deg C but that can be adjusted in the calibration section of the station, once it’s settled down and I confirm readings with the local BOM station here…
So I have no idea what the resistors do, as I haven’t tracked where they’re connected to but that shouldn’t be too hard… Is there a schematic for that Ardafruit board?
Here are some photos of the two units… The
The original unit was hard wired with very short wires, it tore off while I was cutting it free from the glue holding it into its weather shield. I’ve soldered extensions on with sockets for pin headers to make replacement easier going forward. As you can see on the board there are no surface components (and none on the reverse), the pins were retrieved from an old CD drive as I didn’t have a pin header handy but some broke away as the lands are so fragile.
I’ve cut the link bridging the diode on the Ardafruit and it’s still working OK, so in good conditions the diode isn’t a problem. I imagine it may become an issue if the supply voltage dips due to extended overcast weather so I’ll re-instate it later. I’m calibrating the new sensor against the internal sensor, the radings are now within 0.5 deg C of each other but I’ll reinstall the board in the weather screen before finalising calibrations. I’ll aso need to put some confromal coating to protect the board from degradation and a “filter” around the SHT30 to prevent the ingress of dust/debris. The old board was encapsulated in a jacket made out of what looked like polywoven material similar to shopping bags, so that might be the go. Some SHT30 boards I’ve seen have a small PTFE screen mounted on the top face of the IC to do the same job.
And lastly, I may need to replace my old keyboard as I’m noticing a hell of a lot of typos in my posts with letters repeated and I’m reasonably sure that’s not just my fingers…
