Suggestion for a device that senses voltage? Septic Tank Alert


I have a septic tank and a manual alert system (buzzer) essentially a wire connected to a float down in the tank closes the circuit and sets off the alarm. I'd like to keep the manual audible alarm but also add a device that can send a notification when this goes off. Anyone ever done this? A device that can sense voltage being turned on?

My other thought was a sound device strapped right to it (it's loud) but that seems hoaky. So does a bunch of wires and relays. Was hoping someone knew of something...obviously needs to work in HE.

From the manual:

Switching mechanism operates on low voltage and is
isolated from power line to reduce possibility of shock

Can be use with any UL Listed / Recognized switching
mechanism rated to include 1 amp, 12 VAC load


across the buzzer, add the coil of a 12vac relay. Now you have contacts that can go into many Door Sensors. They often have an internal pair of screws to use for just such a purpose.


This escalated quickly tonight... sooooo I went down to measure the actual voltage...while I'm there I find out that the manual alarm was plugged into a UPS...and that had died (ironic right) and the whole alarm was dead. Plugged it in and got an alarm. Yep you guessed it! Wires had shorted in the tank and tripped the breaker for the pump. So the whole reason for an alarm....poof. Just spent the last hour fixing that.


Per your original message, you have 12vac... This connects to a buzzer with a switch on one leg. When the switch closes, there's 12vac across the buzzer. If you purchase a 12ac relay, connect the coil across the 2 buzzer wires. Now, when the switch closes, there's 12vac across BOTH the buzzer and the relay's coil, energizing both. The buzzer buzzes, the relay goes click.

The contacts of the relay are what are called "dry contact" meaning no voltage. (Remember when electricity was called "juice"? Yea, 'wet' means has Juice, 'dry' means no Juice.) The Ecolink door sensor In my pics have an internal port for dry contacts. Meaning the Ecolink has voltage and when the relay's contacts close, it will see that and send a ZWave message.


Was just pulling the parts together to test this out.


Decided to make my own as I didn't have a 12vAC relay. Took a 12v (AC/DC)transformer run through the float to a 12v DC relay. Used the contacts to drive a Monoprice Garage door sensor (has dry contact input). Last step will be to find a proper 12v DC buzzer.


Just be aware we are talking about 12VAC and not 12VDC here.


yep, hence me not having any 12v ac relays and only some 12v DC relays (automotive) laying around. That's why I used an AC/DC transformer. (and why I couldn't use the buzzer). I see above I wasn't clear on that. I'll fix it.


You don't have to fix anything above. I am just pointing it out incase your meter is on DC measurements and get no voltage that's all.


Fixed properly with 12vAC relay DPDT. One set of contacts drives the monoprice sensor, the other set drives the original buzzer/light.