Reply To: Logging data from Milone eTape

Hi Eric. this is a voltage sensor, so it fits a pretty basic type of sensor, measure the voltage and then translate it to depth.

For a sensor, layers of calibration give value. Calibration of the sensor to defined units (V to mm), and calibration of the water height to the measured height in the flume.

The accuracy sounds pretty reasonable, for a visual check can probably can only get to +/ 1mm visually under ideal circumstance.  There are some good ideas of attaching the sensor into the water https://www.envirodiy.org/knowledge-base/ Sect 7.3.4 – however each time is going to require mapping to a physical measurement tape line. So how to secuse the milone tape in a a protective pipe and also relate to its calibration. Might be an idea to have a see through protective plastic pipe, to map milone tape measurements to external physical reading

For the milone tape output, the auxiliary ADC. ADS1115 gives the most accuracy with an input over 0 to 3.3V. You need to decide if running it at switched 3.3V or boosted 5.0V.   I would think 3.3V

I did see this discussion, that is using a 0-10V , but would need to scale it to 0-3.3V

https://docs.google.com/presentation/d/1LqyQEa3EJx3xvbQfo6V8wqlVyj3OxlF3AZsk2E7ZLn0/edit#slide=id.g149c4d18368_0_1

https://envirodiy.github.io/ModularSensors/group__sensor__ads1x15.html

I should point out that main ModularSensors is a “scientific software” package – best effort architecture. Nobody is sharing metrics as to how well it works, which is usual practice for engineering types. Engineering is about high reliability, software and hardware.  There are some good software examples, but no standard software reference builds. If there is good wireless cell signal,  then readings on the server (assuming MonitorMyWatershed ) gives a good visual that the site is operational If the wireless or server becomes unavailable, readings are dropped – however its accessible on the loggers uSd card.  If the available power in the battery gets low and not managed the processor starts resetting and needs a site visit and new battery. So I recommend one of your sensor be the battery and also the  SampleNumber – a linear number increments each sample and reset to 0 when the processor boots. https://envirodiy.github.io/ModularSensors/group__sensor__processor.html

I’ve done my own fork of ModularSensors to make it as reliable as a “Walking Boot Net”, that is walking up to the logger and copying the uSD to get ALL the time series readings. Features here  https://github.com/neilh10/ModularSensors/wiki/1a-Feature-notes

Description of my systems that have been operating in the field for some years https://www.envirodiy.org/n-ca-mayflys-through-the-winter-storms/ 

I did do a crude Electrical Conductivity sensor – measuring the waters EC through a simple sensor, and no wireless – I don’t think this is going to be that helpful but this is where it is – https://github.com/neilh10/ModularSensors/tree/release1/examples/tu_ec01

Goodluck