A Sonoff Elite is used in much the same way as a Shelly device. Because it requires a separate AC power connection, and it bigger, it is a bit more complicated to install.
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Additional Requirements:
See the diagram: https://imgur.com/W8PoOOU
Adapter RJ9
VCC 4 (VCC)
Data 3 (Signal)
GND 1 (Ground)
The Dry contacts on the Sonoff COM and NO should be attached to Input and GND2 using the 2-conductor cable. (It doesn’t matter which wire goes where).
You will need to route the wires through the control panel box. Make sure that you feed the cables through a cable gland (nut).
There are two options for powering the Sonoff. Either use a separate AC plug, or else tie into the pump’s power. If you go the second route, that it would require drilling another hole in the steel cage for the Sonoff power cord. Use another cable gland for this cable.
The unit itself should be either installed outside of the Hydromate or possibly on top of the of the control panel enclosure.
It is possible to control the Softub without the adapter board, if you don’t require returning the temperature from the Softub.
To install this, you don’t need the RJ9 cable, but just use the 2 conductor cable, and install it on pins 5 and 8 on J9. It doesn’t matter which wire goes to which pin To attach to the post, one option is to use female jumper wire with one side cut off, and attached to the cable with Wago nuts.
The cable attaches to these posts: ![assets/sonoff-direct.jpg]