Step by Step
Shelly 2 and Shelly 2.5 have integrated power meters, which detect the consumption during movement and when the roller reaches final position. During movement rollers normally consume around 5 Watt to 2000 Watt. Most of the time consumption is more when opening, than when closing because the resistance is higher. When the roller reaches the final top or bottom (Left or right) position there are an integrated micro switches that cut the power to 0 Watt (in most of cases).
The consumption of a tubular motor, electronic shutter belt, or others, in works must be at least 4 watts, so that the calibration can be completed successfully.
Settings before calibration
The Shelly 2 or Shelly 2.5 should be in Roller Shutter mode.
Settings: DEVICE TYPE: Roller Shutter
1. First check if the power consumption works correct
Open and Close your roller from the App or from the internal WebUI and check are there any measurements. If not, contact with our support, is it possible that your device has a problem with the power consumption chip or firmware issue.
Email: support@shelly.cloud
2. Settings: OPEN/CLOSE WORKING TIME
The real running time of the shutter motor for HIGH and DOWN (OPEN / CLOSE) should be determined prior to calibration.
So that the calibration does not stop, the double running time of the determined real runtime value should be set.
3. Safety: OBSTACLE DETECTION
During calibration disable this Option!
4. Settings: POSITIONING CONTROLS
This option must be activated!
5. OPEN (HIGH) shutters completely!
Calibration
The calibration begins with the activation of the CALIBRATE button in the Shelly app or in the internal WebUI.
When power consumption reaches 0 Watt, Shelly knows that TOP-position is reached and calibration begins.
Shelly changes direction and closes the roller, at the same time measures power consumption and counts the time.
Then again, when the final position (CLOSE) is reached and power consumption is 0 Watt, Shelly remembers that timing and starts opening the roller shutter again. When the final position (OPEN) is reached and power consumption is 0 Watt detected, Shelly remembers this time period again.
The last action is restored to the last position of the roller from which the calibration began.
If the calibration was successful, the Shelly confirms this with a note. 
Trouble Shooting
1. Check all steps "Settings before calibration"!
2. Some rollers do not cut power measurement at all
- The OPEN / CLOSE WORKING TIME should be set to a sufficiently high running time.
- The shutter, although in the final position, "moves" only in the Shelly app or in the WebUI. The power could be anything between 2-10W.
Then check the Shelly IP. You can find it in Settings: DEVICE INFORMATION or in the router network settings.
Then open your PC or phone browser and send the "adjusted" power for the end positions to Shelly.
If you roller shutter has 3W consumption, when final point is reached you need to set 5 (+2):
http://192.168.x.x/settings/roller/0?off_power=5 Adjust IP-addresses!
A lot of success!!! 