Short answer: An existing Somfy RTS awning or exterior screen takes a wind or sun sensor with no new control wire to the motor. Use the Eolis RTS 24V kit for wind, the Soliris RTS 24V kit for sun and wind, or a WireFree sensor where no 24V reaches the wall. Program it from a stored remote, set the threshold, then test in demo mode.
One gust can tear an awning fabric and bend an arm. The repair costs more than the sensor, the visit and the programming combined, and the owner calls you first. A wind sensor on an RTS job is a short add when you plan the power and the programming before the truck leaves. This guide covers the retrofit from quote to handover.
Free spec package
Somfy RTS Wind and Sun Sensor Retrofit: 4-sheet drawing set
- SMD-01 system limits schedule with a Somfy source on every number
- SMD-02 awning install detail and sensor schedule
- SMD-03 retrofit riser and 24V wiring detail
- SMD-04 three-part guide spec, BOM and retrofit checklist
Confirm the motor speaks RTS before you quote
Somfy builds every sensor in this guide for RTS motors and receivers. Each one transmits on 433.420 MHz, the same radio the owner's remote uses. A hardwired motor on a rocker switch has no radio receiver, so it will never hear the sensor. Check the motor label, or check that a Somfy RTS remote runs the awning today.
You also need one working transmitter already stored in each motor. Every sensor programming pass starts from that remote. No stored remote means the motor needs its remote set up first, and that changes the scope of the visit.
Our rule: confirm a working stored remote on the first site call and write its location on the work order.
Pick the sensor by power and mount
One question decides the product family. Can you land 24V at the wall with less than 164 ft of cable from the supply? Yes points to the 24V kits. No points to WireFree.
- The Eolis RTS Wind Sensor 24V DC Kit (9012499) handles wind. It mounts on the wall, ships with its transformer and carries an IP 34 rating.
- The Soliris RTS Sun and Wind Sensor 24V DC Kit (9012500) adds sun to the same wall-mount package, also IP 34.
- The Eolis 3D WireFree RTS Wind Sensor (1816081) mounts on the front bar or arm and reads movement in three axes. It runs on 2 AAA batteries, rates IP 44 and reaches 164.05 ft in open field. Somfy also builds it in black (1816082) and off-white (1816083).
- The Sunis WireFree RTS Sun Sensor (9020412) handles sun only on 2 AA batteries, IP 34, with eight threshold levels.
Rain on a screen or pergola job calls for the Ondeis WireFree RTS Rain and Sun Sensor (9019617). It runs on solar power, senses rain optically, offers six operating modes and rates IP 55.
Power and cable limits for the 24V kits
The Eolis RTS and Soliris RTS 24V sensors run on 24V AC/DC from a Class 2 transformer and draw 25 mA at 24V DC. The terminal block lifts out for wiring and the input is not polarized, so a swapped pair does no harm. Keep the cable between supply and sensor at 164 ft or less. Somfy rates both sensors for -4 F to 122 F.
Somfy's instructions call for the power off and the transformer fully discharged before the final connection. The 120V outlet or J-box that feeds the transformer is line-voltage work, done by an electrician to NFPA 70.
Our rule: measure the cable path on the first visit, drops included. A run that lands at 170 ft becomes a WireFree job, and you want to know that before you order.
Somfy RTS sensor retrofit: numbers to hold
- 6 to 31 mph wind threshold on the Eolis RTS and Soliris RTS 24V sensors
- 0 to 50 kilolux sun threshold on the Soliris RTS 24V sensor
- 2 s from wind over threshold to the UP order
- 30 s after wind drops before the remote works, 12 min before sun automation resumes
- 164 ft max cable from the 24V supply to the sensor
- 25 mA at 24V DC from a Class 2 transformer, input not polarized
Set thresholds the owner can live with
Each sensor sets its trip point a different way. Put the setting in the O&M so the next tech starts from a known value.
- Eolis RTS and Soliris RTS 24V: a wind potentiometer from 6 to 31 mph. Soliris adds a sun potentiometer from 0 to 50 kilolux.
- Eolis 3D WireFree: a dial from 1 to 9, with 1 the most sensitive. Somfy's instructions set it to 4 at install.
- Sunis WireFree: eight levels from 1 kLux to 100 kLux. The LED shows the level, red blinks for levels 1 to 4 and green blinks for levels 5 to 8.
Our rule: start in the middle of the range and adjust after the owner has seen a week of weather. A trip point set too low retracts the awning on every breeze. Too high and the fabric takes the hit.
Know the timing before the owner calls it a fault
Wind has priority over everything. Somfy's 24V instructions spell out the sequence:
- Wind over threshold: the motor gets an UP order after 2 seconds.
- While wind stays over threshold, Somfy blocks every command, manual and automatic.
- Wind drops: the remote works again after 30 seconds. Sun automation stays off for 12 minutes.
- Sun appears (Soliris): DOWN order after 2 minutes. Sun leaves: UP order after 15 to 30 minutes, depending on how long the sun was present.
A remote that does nothing for 30 seconds after a gust is the protection doing its job. Show the owner at handover so it never turns into a service call.
Sun automation needs a Soliris remote in the system. Somfy states a Situo Soliris is required to activate the sun function with Sunis, and Soliris remotes switch the sun mode on and off. The Situo 5 Soliris RTS Pure II (1870579) covers five channels with sun control.
Program and test without a second truck roll
- Hold PROG on a transmitter already stored in the motor until the awning jogs. Somfy's 24V instructions call for more than 2 seconds.
- Press PROG on the sensor. The awning jogs again to confirm.
- Repeat for each motor. One sensor stores in several motors, and the Eolis RTS instructions allow up to three sensors in one motor.
- Test in demo mode. On the 24V sensors, turn the wind potentiometer fully clockwise: the threshold drops to a fixed 6 mph and the clear delay drops to 15 seconds. Sunis demo mode runs 10 seconds with sun and 15 seconds without, and times out after 3 minutes.
- Check direction. The remote DOWN button must extend the awning. A reversed direction would extend the awning in wind, so fix it before you leave.
- Exit demo mode. Somfy's instructions say never leave a sensor in demo mode at the end of the install.
To clear old sensors from a Sunis setup, hold the sensor PROG for about 7 seconds until the motor jogs twice, then add the new sensor the normal way.
Write it into the submittal
A retrofit still deserves paper. List each sensor by Somfy reference, the motor it protects, the threshold setting and the remote that controls sun mode. The spec package below carries a three-part guide spec with bracketed fields for those values, plus a checklist your tech can sign at handover.
Take the spec package to your submittal
Somfy RTS Wind and Sun Sensor Retrofit: 4-sheet drawing set
- SMD-01 system limits schedule with a Somfy source on every number
- SMD-02 awning install detail and sensor schedule
- SMD-03 retrofit riser and 24V wiring detail
- SMD-04 three-part guide spec, BOM and retrofit checklist
FAQ
Can one Somfy wind sensor protect several RTS awnings?
Yes. Somfy's Eolis RTS instructions allow one sensor to be stored in several motors. Run the programming pass once per motor, starting from a remote already stored in that motor.
Does a Somfy wind sensor need a wire to the motor?
No. The sensors talk to the motor over RTS radio at 433.420 MHz. The 24V kits need 24V power at the sensor only. Eolis 3D and Sunis run on batteries and Ondeis WireFree runs on solar power.
Why does the awning ignore the remote after a gust?
Somfy blocks all commands while wind stays above the threshold. The remote works again 30 seconds after the wind drops, and the sun function returns after 12 minutes.
Do I need a Soliris remote for sun automation?
Yes with Sunis WireFree. Somfy says a Situo Soliris is required to activate the sun function, and Soliris remotes switch the sun mode on and off.
Sources: somfysystems.com product pages 9012499, 9012500, 1816081, 9020412 and 9019617; Somfy Eolis RTS 24V sensor installation instructions (ref. 182450A); Somfy Soliris RTS 24V sensor installation instructions (ref. 182449A); Somfy Eolis 3D WireFree RTS instructions; Somfy Sunis WireFree RTS installer manual; store.somfysystems.com Situo 5 Soliris and Sunis bundle page.
Ryan Towns writes the Somfy Integrator Guides for ShadeMotorsDirect, an authorized Somfy distributor. Questions on a spec or a retrofit: 859-414-6872 or colin@shademotorsdirect.com, 8:00 AM - 7:30 PM ET.
