One-Wire Temperature Sensors
I absolutely love One-Wire sensors and have made liberal use of them in my bus.
A One-Wire device communicates via a single signal pin and can work up to 200ft with twisted pair wiring. So just three wires to handle signal, power and ground that works as a distributed electrical sensor bus.
Here's how they are hooked up to my Raspberry Pi controller for the bus:
https://www.crystalpoint.com/cpdownl...ds/OneWire.jpg
Another value point is that they are less than $3.00 a sensor for general use and around $20.00 for the inline liquid temperature sensing.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Note for the liquid sensor you want the 30mm version to use on a 1/2 pipe tee.
Each sensor has a unique ID that must be determined by adding one sensor at time and determining which id is the new one.
Here's the twelve sensors that I currently have installed in my bus.
//
// One Wire Id's DS18b20 Temperature Sensor
//
4D18940B0000 Hydronic output
1B6EE10B0000 Diesel boiler output
AA8B11481401 Generator Bay
AA35AF481401 Fresh Water Tank
AAF6A0481401 Forward Bay
AAC09E481401 Mid Bay
AA01BF471401 Battery Bay
AAE595481401 Plumbing Bay
F854950B0000 Engine Coolant (heater hose input to Glycol Heater/Tank 2)
AA9EA9481401 Under bus outside air temperature
AAF58F471401 Refrigerator
AAA09A481401 Freezer
This makes it very easy to monitor/alarm or automate desired functionality.
Inverter Node-Red Automation Bling
I just added my first bit of automation bling to manage the AC power inverter on my bus.
https://www.crystalpoint.com/cpdownl...verterFlow.jpg
I have a high power inverter 6KW (up to 18KW surge) that has a standby consumption of about 100 watts. So if it is left on 24/7 it will use 2.4KW of power. Given that my house battery bank currently stores about 9KW, that can be a major chunk of the out of the storage capacity.
Obviously not as much of a problem when the sun is shining and is generating solar power.
So anyway this node-red flow monitors the inverter while it is on and automatically shuts it down; when it has been idle for ten minutes. If there is a large draw it automatically extends the time period.
The bling aspect of this flow is that it is Alexa enabled!!! Alexa responds to the following commands:
Alexa, inverter on
Alexa, inverter off
Alexa, inverter status
Alexa responses OK to the off and on commands. For the status command it says OK and then does an announcement with the current status.
https://www.crystalpoint.com/cpdownl...tatusAlexa.jpg
When it automatically shuts down the inverter; it does another announcement "Ding, message". On my Alexa show it also shows the text besides speaking it.
https://www.crystalpoint.com/cpdownl...flineAlexa.jpg
Note: Since all your Alexa devices are in group. I can command things to happen on the bus while I am at home...