Detecting spinning wheels in a aquafarm

Projects General Guidance
1

There are several big ponds (2.000 m2 each) outdoor for fish/shrimp farming. And each ponds have 10 spinning wheels to generate oxygen.

If we are to detect:

  1. whether spinning wheels are OFF (because of no electric or broken machine/motor)
  2. water level if drop below certain point

And it will then notify the users such problems via email/twitter/sms or others.

What are the best/feasible approach for this project? I am thinking there would be 11 arduino + 11 sensors attached to the spinning wheel for each pond. But my concern is the placement of the arduino (and its PSU) since the wheels are in the middle of the ponds. Or I can just detect whether the spinning wheels are using any current ampere? If no ampere, then the machine/motor are broken. This way, I don't need to install the arduino in the middle of the ponds. But is this right?

And also the cost, since there are hundreds of spinning wheels, maybe there is another solution that is simpler?

Thanks

2

fendytan:
Or I can just detect whether the spinning wheels are using any current ampere? If no ampere, then the machine/motor are broken. This way, I don't need to install the arduino in the middle of the ponds. But is this right?

Looks reasonable to me. The required circuitry depends on the motors, what voltage, AC/DC?

In the simplest case a resistor and opto coupler will be sufficient for each motor, provided that the voltage drop of about 2.5V is acceptable. Otherwise current sensing modules are available. Port extenders allow one Arduino to monitor any number of sensors.

3

DrDiettrich:
Looks reasonable to me. The required circuitry depends on the motors, what voltage, AC/DC?

In the simplest case a resistor and opto coupler will be sufficient for each motor, provided that the voltage drop of about 2.5V is acceptable. Otherwise current sensing modules are available. Port extenders allow one Arduino to monitor any number of sensors.

The motors are AC. Which current sensing module is needed? How about this one? Thx

4

That sensor is usable, but have a look at the current range - how much current do your motors draw? It's designed as a removable item, you may find other sensors for permanent application, of easier construction and consequently lower price.