I figured I would post this here for those who don’t frequent MySensors.org
Complete Project Page With Pictures and Everything…
Project Complete! My EH40 has now been ‘MySensored’
This was a fun project, and I learned quite a bit during the process and I was able to accomplish all my goals.
Goal Recap
- Remotely lockout the EH40’s schedule.
- Remotely Activate the EH40 Relay.
- Locally override_to_On, Both Vera and the EH40 schedule (Button)
- Remotely acquire water heater’s tank temperature.
Final Components Used:
- Arduino mini 5V
- Dual Relay 5V]
- Couple of pcb’s
- Screw Connectors
- Push Button
- Temperature Sensor
-
Radio
8.) Step Down Module - Fused Rocker Switch
-
Transformer I wound up going with one of these over the Ebay China option. Just felt more comfortable with this.
11)Project Box
Misa: Resisters, 47uF cap for the radio, wires and lots of solder and hot glue.
Final EH40 Wire Configuration
SEE PICS HERE IN MYSENSORS.ORG THREAD
- Red - 1.5vdc directly from EH40 Batt.
- Black (Yellow) GND
- Blue (Blue) Input
- Yellow (Blue) Output
Transformer Assm: Board
SEE PICS HERE IN MYSENSORS.ORG THREAD
The output seem stable enough (using a volt meter) I didn’t use any post filtering. (EDIT: I added a 47uF cap to the output and 0.1uF to Relay, and Sensor VCC and GND)
All connection under pcb is covered in a thick layer of hot glue to help prevent any shorts.
EH40 Connection Board
SEE PICS HERE IN MYSENSORS.ORG THREAD
Main Control Board
I forgot to get pictures of the top, but here is the messy bottom…
SEE PICS HERE IN MYSENSORS.ORG THREAD
EH40 Connection Board Mounted In Box
SEE PICS HERE IN MYSENSORS.ORG THREAD
Using a Dremel; cut a slot out, then hot gluing to bottom of box.
Dual Relay Mounted
SEE PICS HERE IN MYSENSORS.ORG THREAD
It was a perfect fit.
Push Button and LED (Wired Relay Contacts)
SEE PICS HERE IN MYSENSORS.ORG THREAD
Top relay is #1 (Lockout); 2nd is #2 (Override)
1)Relay #1 – Blue Wire – Output to NC
2)Relay #1 – Yellow Wire – input to COM
3)Relay #1 – Blue Wire – Output NC JUMPED to COM of Relay #2
4)Relay #2 – 2 Red Wires (One from EH40 and the other for battery monitoring on Main Control Board) – Output to NO
5)Relay #2 – COM JUMPED to Relay #1 NC
Fused Power Switch and Socket
SEE PICS HERE IN MYSENSORS.ORG THREAD
500ma Fuse with all exposed connection covered in hot glue.
Transformer; Relay; EH40 Connection and Main Board
SEE PICS HERE IN MYSENSORS.ORG THREAD
I tried to keep the High Voltage section isolated from any of the low voltage section as best as possible.
Completed Project Connected to EH40
SEE PICS HERE IN MYSENSORS.ORG THREAD
EH40 Connection
SEE PICS HERE IN MYSENSORS.ORG THREAD
115vac Connection
SEE PICS HERE IN MYSENSORS.ORG THREAD
EH40 Has Control and running it’s schedule
SEE PICS HERE IN MYSENSORS.ORG THREAD
Vera (Remote) has EH40 Schedule Locked Out (Water Heater Off)
SEE PICS HERE IN MYSENSORS.ORG THREAD
Vera (Remote) has EH40 Schedule Locked Out but Override button is active (Water Heater On)