I built a project and am hoping somebody would be willing to peer-review it. This is my first post to this forum so my apologies if this is located in the wrong place.
I have an old 1977 marine diesel that lacks decent monitoring. It only has engine temp, oil pressure and a wildly inaccurate tachometer. I built a monitoring system based on the Uno R3.
The system uses six DS18B20 sensors for locations that do not exceed 250F:
- Raw water entering
- Raw water exiting
- Coolant entering heat exchanger
- Coolant exiting heat exchanger
- Cylinder head temperature
- Engine room temperature
There are also two thermocouples connected to MAX31850 amplifiers:
- Oil temp
- Exhaust gas temp
The DS18B20 sensors are on a dedicated 1-Wire bus and the MAX31850 amplifiers are on a separate 1-Wire bus.
The RPM is sensed by a SainSmart hall switch with a small magnet on the flywheel.
There are three enclosures:
- Main enclosure contains the Uno and the MAX31850 boards
- Dash-mounted enclosure contains a 16 X 2 LCD and a "next’ button. Pressing the next button shows the next sensor
- Hall sensor is in a small plastic enclosure the size of a tic-tac box and mounted on a bracket near the flywheel
All the sensor leads run to the main enclosure. The dash enclosure is connected to the main enclosure with a length of CAT5/6 cable.
Attached are the code and Fritzing diagram.
The code and documentation live at bitbucket at R_P_Ryan / EngineMonitor / wiki / Home — Bitbucket.
Any feedback would be appreciated.
EngineMonitor.ino (4.24 KB)
ZSensor.cpp (1.94 KB)