Electric water heaters are a common appliance in many households. They provide hot water for bathing, washing dishes, and laundry. However, they can also be a significant source of energy consumption, particularly if they are left on for long periods of time. Automating an electric water heater can help reduce energy consumption, save money on electricity bills, and make the appliance more convenient to use.
One way to automate an electric water heater is by using a Shelly 3EM device combined with a 2 pole normally closed contactor. The Shelly 3EM is a small, compact device that can measure the energy consumption of up to three separate electrical circuits. It is designed to be installed inside a din rail electrical enclosure, and it connects to a Wi-Fi network, allowing it to be controlled remotely using a smartphone or other device.
A 2 pole normally closed contactor is a type of electrical switch that is designed to control the flow of electricity to a split single phase or two phase circuit. When the contactor is closed, electricity flows through both poles, and when it is open, the flow of electricity is interrupted. In the case of an electric water heater, the contactor can be paired with Shelly 3EM and then used to turn the appliance on and off automatically, based on time of day, certain conditions or triggers.
To automate an electric water heater using a Shelly 3EM and a 2 pole normally closed contactor, follow these steps:
Turn off the power to the electric water heater. This can usually be done by turning off the circuit breaker that supplies electricity to the appliance.
Install the Shelly 3EM device inside the electrical panel. This will require some basic electrical knowledge and tools, so if you are not comfortable with electrical work, it is best to consult a licensed electrician. The Shelly 3EM should be installed according to the manufacturer’s instructions, which will typically involve connecting it to the appropriate electrical circuits using wires.
Connect the 2 pole normally closed contactor to the Shelly 3EM device. This will also require some basic electrical knowledge and tools. The contactor should be connected to the Shelly 3EM using wires, and it should be positioned so that it can control the flow of electricity to the electric water heater.
Configure the Shelly 3EM device using the manufacturer’s app. The Shelly 3EM device should be connected to a Wi-Fi network, and it should be configured to measure the energy consumption of the electric water heater circuit. This can usually be done by selecting the appropriate circuit in the app and following the on-screen instructions.
Configure the Shelly 3EM device to trigger the 2 pole normally closed contactor. This can be done using the app, and it will typically involve setting up a rule or automation that tells the device to turn on the contactor when certain conditions are met. For example, you could set up a rule that turns on the contactor when the energy consumption of the electric water heater circuit exceeds a certain threshold.
Test the system to make sure it is working properly. To do this, turn on the power to the electric water heater and wait for it to heat up. Then, use the app to check the energy consumption of the circuit and make sure it is being measured correctly. You can also test the contactor by manually triggering it using the app and making sure the electric water heater turns on and off as expected.
By following these steps, you can automate an electric water heater using a Shelly 3EM device and a 2 pole normally closed contactor. This will allow you to control the appliance remotely, reduce energy consumption, and save money on electricity bills. It is important to note that this type of automation requires some basic electrical knowledge and tools, so if you are not comfortable with electrical work, it’s best to either hire an electrician or wait until you’re more familiar with electrical wiring.
One quick note – if you don’t need energy metering, just automation, use Shelly Pro 1 instead of Shelly 3EM for big cost savings!