I need help. I have a Liberty ALM-2W Lift Pump alarm. It is pretty simple. It has 120V power (US) and two wires from the secondary float. When the secondary float gets too high, it closes (or opens - I am not sure) the circuit and the alarm goes off. My goal is the place a Shelly or something in the box so that I can also get a notification in home assistant that the alarm is going off. What is the best/easiest solution?
Probably the simplest way would be one of these:
https://www.shelly.com/en-au/products/shop/shelly-1-mini-gen-3
You connect up the Shelly power and switch and ignore the relay output.
It will create a binary sensor in Home Assistant that turns on when your axillary contacts close.
Connect 120 volts to the sw input on the Shelly 1 through the N/O contact on the lift station alarm. That way when the lift station goes into alarm mode the N/O contact will close and switch the Shelly to “on”. You can setup an automation for this status change.
This is what I ended up doing and it seems to be working great. It has been up and running for about two weeks with no issues. The system even lost power yesterday for about 30 seconds and the notifications worked as well.
I found in the owners manual this bullet which I took to mean that I can put 120V mains (here in the US) through the N/O or N/C switch.
So I wired it up like this:
The Alarm is powered from 120V Mains which runs to L1 and L2/N on the panel. It also has a connection from the secondary float switch connected to the two float switch terminals on the alarm. I connected the Load (normally black wire) to L on the Shelly 1 and to L1 on the Alarm. I also connected this same wire to the normally open (N/O) on the panel. I connected the Neutral (normally white) to the L2/N on the Alarm and N on the Shelly 1. Lastly, I connected the SW to the Comm port on the Alarm. The Shelly integrates right into Home Assistant. You do have to make sure a couple of settings are correct for the first generation Shellys, but all that is in the home assistant documentation for Shellys. Also, you need to make sure the jumper on the Shelly is set for 120V.
I can now be notified if the Alarm loses power. More importantly, I will be notified if the secondary float switch is activated which will change the normally open switch to closed on the alarm and in turn switch the shelly. The primary float switch activates the pump, but if the pump stops working and the tank fills up then the secondary float switch is activated and the alarm sounds. My next job is to place something similar on the primary float switch and pump. You can press the test button on the Alarm to check your notifications and setup.
Thanks for all the help. I know there are other ways to set this up, but this seems to work well for me.