I am thinking that at the time when (or if) this configuration become available for commercial and a certification is needed, It would make sense that I would look into getting certification for it.
I think attaching something to your a smoke detector is not out of the question as mentioned by @parish99. It is more of the questions of whether there is a certification is needed.
At this point, it is just an idea. It is a prototype to show whether combining the environment sensor and the monitoring of the smoke detector is make sense. Does the reward of convenience worth the effort to get clearance from any jurisdictions?
As for pioneers, I think this is a good time to share some additional technical design in the aspect of making the module safe to use. I mentioned on the other thread that the smoke detector monitoring is based on Dr Edward Cheung. He used an optocoupler to isolate the interconnection to the monitoring side. This is probably as safe as you can get. The reliability of an optocoupler is perhaps order of magnitude of a mechanical relay.
On the power supply side. The AC converter is protected by 0.2A fuse. This is to ensure that we are drawing minuscule amount of power with today standard. There is also 70 degree C thermal fuse just in case. There is also Varsistor to protect the power side from voltage spike. There is also more than enough separation between DC and AC side.
If you open up one of these real smoke detector, I wonder whether they are even taking care the safety of the power supply side this much.
Adding to me being yet another person who would buy one of these from you. Not just because I really need and want it (I do), but I'm am equally a huge fan of supporting tinkers and really appreciate what you are doing here!
Thanks for contributing in making this community so awesome. While HE is very cool in and of itself, what is making me love it is this community.
@iharyadi can you let me know the size of the PCB board for this? I am trying to figure out if it will fit in this (might need to adapt to use size box) so I can make all the smoke detector in the house smart by adding one of your PCB under an existing smoke detector.
I just want to announce a new expansion capability for future build of Environment sensor. I am adding a serial port to the Environment sensor. The data from serial port will be tunnel through Zigbee to/from the Hubitat hub. I have a video about this new feature. My intention is to enhance the capability for all of use to expand the sensor to handle more complicated sensor using an external MCU.
Here is a youtube video interfacing with Load Cell and Dust sensor.
I will be sharing more exciting capability with the serial port in the coming weeks.
I am excited about he possibility that may be open up. I want to thank every one here who has supported my project.
@ogiewon, I have not forget about sending you a module with serial port access. I will send you one shortly for you to play around with.
I printed the box and I don't think it's going to fit the PCB. Will need make it a bit bigger. I have the PCB coming so I'll design a new box to the correct size once I have it.
@iharyadi, please consider adding mounting holes for the PCB.
I will. The PCB for the bigger board with AC power has mounting hole on the original gerber. The PCB maker removed them. I have notify them about the issue. I will pay attention if I make this version again. Thanks for catching that.
Let me know when you design something, I'd like to use it as well for the unit I purchased. I may try to make a PCB protector to cover the mains connections and I’ll share if I make something usable.
Here is a protector I made. My thinking is I'd add screw points to this to connect it to whatever enclosure sits between my smoke alarm and the ceiling. Zigbee Protector v2 | Tinkercad. I don't plan on putting a battery into it.
I hope you guys stay safe and healthy during this time.
I would like to announce formally a new functionality for the module. I am exposing a USART (serial port) expansion so that it can be interconnected with another MCU. This functionality allow us to add more complex sensors. Here is an example you can do with it.
I want to let everyone know that I have 10 modules available to share. This time I have the module assembled by a manufacture in a test run. The result is very encouraging. The yield is quite good. The build quality is much better than what I can do.
If you are interested on one of this modules, please PM me. Some of you have reach me before, I will try to remember you. However, please remind me if you can. I only have small quantity.
However, these are a test production run which mean that future availability at higher quantity is on the horizon.
I would like to take this opportunity to thanks everyone who has help on the project.
I'm trying to figure out what units the pressure reading is in. I see in the driver code that kpa is listed but my sensor is reporting 84.6 which would be 24.98 inhg. That can't be right unless I'm in the eye of a hurricane and it doesn't look like it out my window
Just one, Iman. I'll get to the others tomorrow... hopefully. This is not an important reading to me as I don't see the need for pressure. I just like to check gizmos out and understand them. I"ll post a table of the readings from each board when I can.
Hi Steve, thanks for letting me know. I like to know it anyway. This batch is built by a manufacture. I am testing their yield. If this is a damage sensor, I really want to know so that I can plan for the future in term of yield.
I just did smoke test. I pair the sensor on my development hub. I looked at the values quickly to see whether they are unreasonable. I do not recall any of the sensors that I sent you have any strange reading. However, I could miss it.
If this is only one of them, I can fix it for you if you send it back to me. I can just replace the sensor.
Thank you, Iman, but that won't be necessary. Even if I do decide I want atmospheric pressure for something I can simply use one of the others. It's not like it varies on my property.
Curiosity got the better of me so I got the readings from all the sensors. For reference, I put my ThermoPro base station close to where the sensors are plugged in and it says:
humidity : 34
temperature : 70.0
The pressure I got from the National Weather Service:
Barometer 29.7 in (1005.76 mb)
which equals 100.58 kpa
Note: I'm at 4700 ft elevation here
I don't know why the pressure would read so much lower unless the NWS somehow adjusts for elevation. My wall barometer is reading 29.5. At least they are consistent so I'm good.
Hmm, interesting. The pressure does not look like a sensor issue. I am around 550 feet elevation. I am reading around 99 to 100 ish KPa. Perhaps, your elevation of 4700 feet would make the pressure reading lower than expected.
The temperature reading is as my expectation. The Zigbee repeater is power up all the time. This will contribute around 1 degree Celsius offset. In the device page, there is a way to adjust the temperature if you like. I personally not do that.
Relative humidity has tendency to be reading low in the beginning. Eventually, they will settle down. The Bosch 280 may need to go through reconditioning process. They went through re-flowing after all.
