First post so please go easy on me, if you need any extra information please just ask. I am completely new to electronics but I am a mechanical engineer by trade with some limited electronics circuitry experience, looking to expand my knowledge.
I wanted to get your thoughts on feasibility on a homebrewed project. I am basically wanting to life time cycle a fan when it meets certain criteria. This is to act almost as a preventative maintenance so I can swap the fan out once it meets a total run time or number of revolutions.
I am hoping to do this with an Arduino Nano 33 IoT and a A3144 Hall Effect sensor with a 10k pull up resistor (commonly seen in pretty much all tacho arduino projects), coupled with two magnets for detection of RPM. I have produced a circuit and checked the function to ensure that the hall effect sensor can detect magnetic field by getting it to turn on the built in LED.
The device will be battery powered so low power consumption is required, measured variables to be sent via BLE or IoT (dependant on ease of code power consumption etc).
Measured Variables:
Total time in operation (since power on switch & min rpm met)
Total number of revolutions (since min rpm met )
Operation:
Only when RPM is equal or greater than 100, count time (Hours:Minutes) and number of revolutions. This is to be a summation since power on switch.
When RPM is equal or lower than 99 , stop counting time and revolutions.
My questions:
Is the above possible and what data transfer method would be the easiest to "code" whilst having the lowest power consumption? (if i can access the measurements on my phone that would be great)
Is it possible for energy saving reasons to send the data (Total time in operation Sum and Total revolution sum) at specified intervals? say every 30 minutes?
Is it possible within the EEPROM of the board to have a continual save and overwrite of the last two measurements (is this energy efficient?) this is to provide a failsafe record of the measurements should the device run out of power.
If point 3. is possible to have a reset based on the device on/off switch?
Is it possible for it to have "micro sleeps" when min rpm isn't met/ automatic wake from sleep when rpm is equal or greater than 100?
Pointers / info for how to tackle this from a coding perspective as I am as green as anything (what parts of my operation need to go into setup/ loop and in what order).
I know I have thrown myself in the deep end here but I like a challenge and doing something for an application requirement is far more engaging than something random.
The EEPROM would work if you keep moving the storage location on a regular basis, this will even the ware and allow a lot more cycles. You could also use FRAM, It for all practical purposes does not wear out. It is good for billions of cycles. Keep it in locations locations in FRAM and if something interrupts it during a write you could use the remaining locations that match.
I am curious how you are going to keep this going, it appears to me it will run for years. That exceeds the shelf life of many batteries.
If you expect the life cycle to run to months or years, requiring battery-only power leads to an order-of-magnitude increase in project difficulty. Especially for wireless operation!
Advanced coding techniques and electronic circuit design expertise are generally required for success. For the "classic" Arduino Uno/Nano/Pro Mini start reading about that here.
I did play around with some of the Nano 33 IoT tutorials and this board has bluetooth capability - so providing I can find a corresponding app this sounds like it should work - thankyou!
it shouldnt be a huge string - if i can set the variable HHH:MM,Revs and have it output :
100:30, 999999999
I Imagine that is a few bytes if it could do the summation and send every 30 mins that isn't masses of amounts - or does it need to internally count and calculate summation more frequently?
yes I saw that its approximately 10k cycles - it was more of a failsafe if power was interrupted and the connection was lost before it sent the last string. - maybe I can omit this and come back to it later.
fantastic - I am using a dev board currently but may refine and reduce the circuitry on the board for decreased power consumption.
perfect exactly what I was after - I wanted to create individual codes for each part and then try to consolidate afterwards - this will hopefully make it easier to debug !
as above
thankyou - I shall be making some headway with it tonight it seems! thanks!
I think that 9-12 months will be a runtime from failure, with potential to move away from the dev board into a bespoke board for the application, removing parts of the dev board I do not need. This is more POC before I invest in anything bespoke.
thankyou for your input much appreciated! piqued my interest!
thankyou - had a quick skim, this goes down the lines of stripping the arduino and producing a board for the parts I need which i thought might be the case! this is great thankyou!
its mainly down to spatial constraints and sealing - running wires will allow ingress - there is no chance to modify the existing geometry to allow for a cable gland or different cable routing unfortunately.
the sensor and arduino would be measuring through a "membrane" which is why I couldn't opt for a IR sensor or similar.
