Shelly Wifi Devices Frequently Asked Questions

Shelly Wifi Devices Frequently Asked Questions

Shelly Wifi Switches and Sensors Frequently Asked Questions

Can I use a dimming-knob as “SW” input to Shelly devices?

No, we do not advise this. The only thing that should be connected is an ON/OFF switch or a pushbutton, between the “SW” and “L” inputs. A dimmer connected to the “SW” input would not allow dimming as the Shelly products use relays or MOSFET transistors to respectively turn ON/OFF and dim.

Which Shelly products allow dimming?

The Shelly products that allow dimming are Shelly Dimmer2 for 110-220V AC lights and RGBW2 for 12V-24V DC loads.

How Shelly battery-powered devices work?

All Shelly battery-powered devices are at all times in sleep mode. They have a secondary ultra-low-power processor that is measuring the sensors, the battery, and the buttons. In the event of a change in any of the indicators, this processor wakes up the main CPU to transmit the information over the Wi-Fi network.

Which Shelly products measure power?

The Shelly devices that support power measurement are: Shelly 1PM and Shelly Plus 1PM Shelly 2.5 Shelly Pro Series devices Shelly EM Shelly 3EM Shelly Dimmer 2 Shelly RGBW2 Shelly Plug, Shelly Plus S, Shelly Plus US Shelly Bulbs – Duo, RGBW, Vintage

How long do the batteries last in Shelly products that use them?

The battery life of each battery-operated device is stated on its dedicated product page. Each device’s battery life is estimated based on its “out of the box” setting. Customized settings might extend or shorten the battery life.

I have a wind sensor attached to the roller shutter. Would it work with Shelly 2.5?

Shelly 2.5 has roller shutter management and can control the shutter’s engine. Additional sensors (for example: wind sensor) would not work.

What product do I need for garage/gate doors?

Shelly 1 or Shelly Plus 1 is most suitable for use in such configurations. Depending on the motor you might need two devices for each position.

Can I monitor the Open/Close status when controlling the garage door?

Yes. For this purpose you need a reed switch connected to “SW” input or to Shelly 1 temperature Add-On.

I have worries that my devices are getting to high temperatures. What can I do?

The maximum ambient temperature is 40 degrees. With no load, PCB temperature is 55-60 degrees. Heating protection will switch off the device at 95 degrees.

Can I monitor a solar panel?

Yes, that is possible with Shelly EM/3EM.

Can I use different phase/voltage on L1-L4 or S1-S4 on Shelly Pro 4PM?

That is not possible, connecting different phase/voltage to device will harm it immediately.

I have a sprinkler system. What device is required for automating it?

Shelly 1 or RGBW2 are capable for such configuration.

Can I use 50A clamp for Shelly 3EM?

The device works only with 120A CTs and each transformer is calibrated for the specific device port.

Do I need the cloud to use Shelly Cloud App?

We recommend using the cloud for better product expierence. If devices are not cloud enabled, they should be controlled only within the local network.

Can I use the Shelly devices without Shelly Cloud App?

Yes. It is possible to control them locally through the embedded web server of the device (access it by typing the IP of the shelly device in browser) or through MQTT broker.

How many entries are stored in the event log?

The limit is 100 entries and cannot be changed. Also they cannot be deleted, they are overwritten when the limit is exceeded.

My logs are not stored? What can I do?

Logs saved are related to the cloud connection. Please make sure that the cloud is enabled from the application.

Shelly device is shown as offline in Cloud Application, but it is powered. What is the problem?

Check if you can reach the device through IP. If you can reach it, then there is problem with the cloud connection. To fix that, Refresh/Reboot Shelly app and enable the cloud from there. Alternatively, you can make factory reset and start from scratch.

My device has Wi-Fi periodic connectivity issues. What should I do?

Set static IP out of the DHCP range. Pay attention on the RSSI signal. Make sure that you do not have smart features enabled on your router and you are using the best wi-fi channel suitable for you. If problem continues, contact the support for further troubleshooting.

I am not able to add my device to the Cloud. What should I do?

Reboot the router and try adding the device again. If device is still not included successfully, check the IP address of Shelly device and type it in the web browser. Then when WebUI is loaded, check in the right corner if Time tab is working. If not, that means that your device does not have internet connection and problem could be in the default gateway, firewall, DNS etc.

How can I Edit/Delete my rooms?

This is possible after you click on the Settings button in the right corner of your application and then click on the pencil icon.

I am not able to login in the application with my credentials. What should I do?

Set static IP out of the DHCP range. Pay attention to the RSSI signal. Make sure that you do not have smart features enabled on your router and you are using the best wi-fi channel suitable for you. If the problem continues, contact Support for further troubleshooting.

How can I enable the MQTT feature?

You need to check what is the device’s IP address. Then type it in your browser to access the local server of the device. Then enable the advanced developer settings.

Where is my consumption history? It does not show in the application?

To access the consumption history of your device, it is necessary to be connected to the Cloud.

Is it possible to create a scene on certain channel of my device?

The channels of the multi-channel Shelly devices are displayed separately in the application. That is because they are independent of one another and you can create separate scenes for each channel.

How can I share my devices with family members?

Under each device there is a “Share” section. Maximum 5 members can be added to each device.

How to control devices from PC?

Type: in your browser. You will be able to control your devices through the PC.

Should I pay for the cloud services?

No, Shelly’s cloud is free and everyone can use it to control the devices from any location.
How to use MQTT and Cloud in same time for Old generation devices?
The old generation devices does not support cloud and mqtt in same time. The only exception is H&T.

I have installed Shelly Door/Window2 sensor, but I do not receive email/phone notifications. What should I do?

In order to receive notifications when the state of Door/Window 2 sensor changes, you need to create a scene.
My email/phone notifications are not working. What should I do?
To receive email/phone notifications, you need to make a scene and make sure that notifications are enables in the app or the phone settings.

How to add Scenes in Shelly Cloud app?

To create a scene, press the button located at the top right of the screen and select “Add Scene” from the drop-down menu. Type the name of the scene and select the room in which this scene will be located. Then select a suitable picture or upload an image from your device.

The scene is divided into 2 main stages:
1) “When” – refers to conditions that must be met to activate the scene. You can add conditions depending on the type of device or time. Shelly Cloud can support many conditions that must be true to fulfill the scene. If you want to add a condition, you have to press the “AND” button.
2) “Do” – refers to the scene that should be activated given the “When” conditions appear.
For example: (When) If Shelly Motion sensor detects motion after 10PM. (Do) Shelly Dimmer will turn on the lights with 50% dimming.If the performance of a scene depends on more than one factor, you can use “OR”.

What does “condition types” mean in Scenes?

There are 3 condition types, used for different purposes – “One time”, “Repeatedly” and “On any change”.

– “One time” – when the pre-set condition has been reached, the scene will be activated only one time. For the scene to be activated again, the “WHEN” condition needs to be repeated. If you additionally insert a time in the “Condition is valid” field, the scene will not start until the “WHEN” state has existed for at least this time.
– “Repeatedly” –  The “WHEN” state is constantly queried every full minute. And all set “DO” actions are also queried every minute if the “WHEN” state is not changed.
– “On any change” – This condition is mainly used for monitoring temperature or power consumption. When that condition type is chosen for the value of X, it will always activate the same scene when pre-set conditions are met.
(WHEN) Shelly EM detects more than 15W, (DO) Send notification.
In this case, every time Shelly EM detects a power consumption of over 15 W ( > 15W ), a scene will be triggered and the device will send a notification to the app, hence the user.

I have not found an answer for my question. What should I do?
Please contact our Technical Support Team by sending an e-mail to or raise a ticket from here –

Can I use another brand CTs for Shelly EM/3EM?

We do not recommend using different brands.

What is the difference between Shelly Plug and Shelly Plug S?

Shelly Plug has 16A relay, while Shelly Plug S has 12A relay with internal temperature sensor checking for the PCB temperature.

What is the power consumption of the Shelly devices themselves?

It is less than 1W when the relay is on.

Can I control the NG devices through Bluetooth?

No, the protocol is used only for device inclusion.

Is it possible to control 2 devices together, when there is no physical connection between them?

It is possible to control the devices together through HTTP commands – or through app scenes

I see wrong measurement from Shelly EM/3EM. What should I do?

Most often the reason for wrong measurements are wrong wiring. Double-check the wiring and make sure the CT transformers are installed in the correct position.

I have an Air Conditioner. Can I use some of the Shelly relays to turn on/off them remotely?

We do not recommend using relays to switch on/off directly the power supply of the AirConditioner.
I want to control a load above 16A and monitor his consumption. What device should I use?
Our recommendation is to use Shelly EM/3EM with external contactor relay.

My Shelly 1/1PM/2.5 is restarting when switching on inductive load – such as fans, motors, roller. What should I do?

To avoid that a RC snubber should be wired between Output and Neutral of the circuit. Еnergy absorbing circuits are used to suppress the voltage spikes caused by the circuit’s inductance when a switch, electrical or mechanical, opens.

For which Shelly devices can I use Shelly Bypass?

The product is compatible with Shelly 1L and Dimmer 2.

Can I extend the cables from Shelly Add-On / CT transformers?

There is no problem to extend the cables.

Can I use Shelly sensors outside?

Our sensor devices cannot be installed outside because they are not protected from moisture/dust.

Is it possible to use external power supply for Shelly H&T?

Shelly H&T can be powered with battery or with MicroUSB cable only after the USB addon accessory is attached to the device.

What can I use the temperature Add-On for?

The temperature addon is useful for heating automations (when you connect DS18B20 sensor or DHT22 ), water temperature monitoring (DS18B20) or for monitoring the open/close status for your garage door by connecting reed switch to the addon.

Is it possible to control devices with HTTP commands when temporary there is no internet access?

Yes, it is possible. The commands are sent locally and they work even when there is no internet access.

What will happen if my internet drops? Will my Shelly EM/3EM continue to report the energy?

Yes, the device is reporting the energy usage all the time in his internal memory in case a Wi-Fi connection is not available. The data can be downloaded at any time in .csv format.

Can I change the status period update?

The send status period is set on 12H and cannot be changed. The device will still wake up if there are configured temperature or humidity thresholds.

Can I use rechargeable batteries 3.7V CR123A for Shelly H&T/Shelly Flood?

The voltage rate of batteries needs to be exactly 3V. Using higher voltage will damage the device.

How to use Shelly devices without internet?

It is possible to control Shelly devices without internet, but you need to configure own SNTP server, from where they can obtain information about the time.

I am not able to connect to Shelly network. What should I do?

Perform factory reset and make sure that there is no device around you with enabled auto-connection to this Shelly network.

Calibration on Shelly 2.5 is not working. Where is the problem?

Make sure that the engine is AC and you see its power consumption. You can use one Shelly device per shutter. If calibration fails again, use the Shelly Cloud app to increase the Open/Close time to 120s each.

How can I enable the MQTT feature?

You need to check what is Shelly’s IP address. Then type it in your browser to access the local server of the device. Then enable the advanced developer settings.

Why my Smart bulbs are not switching ON with configured “Night mode” after turning them ON via switch?

To obtain the current time and to be able to apply “Night Mode” pre-set brightness limit, Shelly Bulb Duo/RGBW or Shelly Vintage Bulbs need to be constantly turned on.

Can I send HTTPS commands with New Generation devices?

Yes, the new generation devices (Shelly Plus and Shelly Pro series) support HTTP/HTTPS actions.

Can I send HTTPS commands with Old generation devices? No, it is not possible.

What devices are part of New Generation?
All products from Shelly Plus line and Shelly Pro line are Next Generation devices.

Can I send HTTP commands to a Shelly device itself?

Тhe Shelly devices support “local” action URLs. This allows devices to invoke actions not only on other devices, but on themselves as well. To execute a local action, the action URL should be set with a prefix http://localhost/.

Is it possible to use the temperature Add-On from Old generation devices to the NG devices ?

No. The currently available temperature Add-On can be used only for the old generation devices – Shelly 1 and Shelly 1PM.

More Shelly Resources:

Check the Shelly Knowledge base?

Shelly has a dedicated Facebook page for this and has support there.

You can also launch a ticket with them, and they will respond to your enquiry.
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