An exterior zip screen fights wind, fabric tension, and its own side channels, and the motor has to win that fight on the way up and the way down. The Somfy Maestria 525A2 RTS 120V Motor (1134083) is Somfy's answer for that job: 25 Nm at 20 rpm, IP 44 rated, with obstacle detection built into the head.
Sizing 25 Nm to an exterior zip screen
Somfy designed the Maestria 50 RTS range to motorize exterior vertical screens, and the 525A2 sits in the middle of it at 25 Nm. Torque demand on a zip screen comes from four places: the weight of the fabric and bottom bar, the friction of the zipper in its side channels, the wind load pressing on the screen face, and the drag of a cassette hood at the top of the travel.
Those loads add up faster than an interior shade of the same width. A screen that would run on 6 Nm indoors can want 25 Nm outdoors once the zip track and a coastal wind rating enter the picture. Somfy publishes the Maestria range at 6, 10, 15, 25, and 35 Nm so the specifier can match the screen instead of rounding up. The 525A2 covers mid-size patio and lanai openings, retractable insect screens, and hurricane screen assemblies. The Somfy Maestria 525A2 RTS 120V Motor (1134083) carries a 5 year Somfy warranty.
Screens and tubes the Maestria 525A2 drives
Somfy publishes a minimum internal tube diameter of 1.85 inches (47 mm) for the 525A2, with a motor body external diameter of 1.77 inches. That places it in Somfy's LT50 hardware family, which is the same crown, drive, and bracket ecosystem the Altus and Sunea exterior motors use.
Octagonal tube is the common choice on exterior screens, because the flats give the drive a positive key and stop the tube from slipping under a wind gust. The Somfy Octagonal LT50 70mm Crown and Drive Set (9012234) matches a 70 mm octagonal tube, and the Somfy LT50 DS78MM Crown and Drive Set (9012239) steps up to the 78 mm profile used on wider cassettes. Order the crown and drive as a matched pair for whichever tube the screen manufacturer supplies, and confirm the tube profile before ordering, since a 70 mm crown will not seat in a 78 mm barrel.
The 525A2 uses a star head, marked by the A in Somfy's 525A2 designation. Somfy's R designation, as on the Maestria 550R2, marks the round head instead.
Verified specs for the Maestria 525A2 RTS
| Torque | 25 Nm (221 in-lb) |
| Speed | 20 rpm |
| Power supply | 120V AC, 60Hz (108V to 132V) |
| Standby draw | 0 W |
| Radio frequency | 433.420 MHz (RTS) |
| Radio channels | 12 |
| Open field range | 656.2 ft |
| Motor head | Star head |
| Minimum tube inside diameter | 1.85 in (47 mm) |
| Motor external diameter | 1.77 in (45 mm) |
| Protection index | IP 44 |
| Limit switch | Electronic, 250 turn capacity |
| Warranty | 5 years |
Figures above come from Somfy's product record for 1134083 and Somfy's Maestria 50 RTS technical brochure.
Obstacle detection and automatic tensioning
Two features separate the Maestria from a general purpose exterior motor, and both of them address problems specific to zip screens.
The motor senses a load change on the way down and on the way up. Somfy states that the motor detects obstacles in either direction, which protects the screen fabric and whatever sits under it. Patio furniture left inside the drop line is the everyday case. A twisted zipper or a bird nest in the side channel is the case that saves a fabric replacement. The installer can deactivate detection or raise its sensitivity on the downward stroke, and Somfy exposes that adjustment from a halfway screen position during programming.
Automatic self-tensioning handles the second problem. Zip fabric stretches with heat and relaxes with cold, and a fixed lower limit that was correct in March sags by August. The Maestria recalibrates its limits across the life of the product, which keeps the fabric flat and the zipper seated in its track. A screen that seals at the bottom limit keeps insects out, and Somfy calls out precise limit setting as the mechanism behind that seal.
Crown, drive, and bracket hardware for LT50 tubes
The head end needs a bracket cut for the star head pattern. The Somfy LT50 Star Head Motor Bracket (9410651) is the direct match, and it bolts the motor into a cassette end plate or a structural upright. For assemblies where the screen manufacturer wants a captive fit rather than a bolted plate, the Somfy LT50 Universal Bracket with Spring Clip (9420631) holds the head with a spring clip and takes the motor out again without dismantling the cassette.
On exterior work the bracket takes wind load as well as motor reaction torque, so fasten into structure rather than into a hood skin. Salt air and thermal cycling both punish an undersized fastener over a few seasons.
RTS remotes and sun control for patio screens
The 525A2 carries a built-in RTS receiver on 433.420 MHz with 12 channels and a 656.2 foot open field range, which covers a patio and a house from a single handheld. The Somfy Telis 4 RTS Multi-Channel Patio Remote (1810645) is the outdoor-rated handheld for this application, and its four channels drive four screens or three screens plus a group.
Adding a Somfy sun or wind sensor to the same RTS network gives the screen an automatic retract on a wind threshold, which is the feature that protects an exterior screen when the property is empty. TaHoma brings scheduling, phone control, and voice on top of that.
Setting the limits on a Maestria 525A2
Somfy's quick programming guide gives the installer a choice of automatic, semi-automatic, and manual limit setting, and the right one depends on the screen.
Automatic mode finds the lower limit on its own: press DOWN, let the screen reach its stop, and the motor performs a short upward move before returning. The upper limit follows. Semi-automatic mode has the installer drive the screen to the wanted lower position, then press MY and UP together, with the upper limit setting itself afterward. Manual mode sets both stops by hand, MY plus DOWN for the lower and MY plus UP for the upper, and it is the mode to use on a screen whose hard stops are not where the fabric should finish.
Pairing the first transmitter follows the same sequence Somfy uses on Altus motors: a brief simultaneous press of UP and DOWN makes the screen jog. Check rotation direction next, and hold MY until the screen jogs again to reverse it. One caution from Somfy's guide is worth writing on the back of the hand: leave the motor idle for more than two minutes during programming and it drops out of programming mode.
Frequently asked questions
What size screen does a 25 Nm Maestria motor handle?
Torque demand on an exterior zip screen depends on fabric weight, zipper friction in the side channels, wind load, and cassette drag, so width alone does not answer it. Somfy offers the Maestria range at 6, 10, 15, 25, and 35 Nm. The 525A2 suits mid-size patio, lanai, and hurricane screen openings.
Does the Maestria 525A2 fit an octagonal tube?
Yes, with a matched crown and drive set. Somfy publishes a minimum tube inside diameter of 1.85 inches for this motor. A 70 mm octagonal crown and drive pairs with a 70 mm tube, and a 78 mm set covers the wider cassette profile. Confirm the tube profile with the screen manufacturer before ordering.
How does obstacle detection behave on a zip screen?
Somfy states the motor detects obstacles going down and going up, which protects both the fabric and anything beneath the screen. Sensitivity on the downward stroke can be raised, or detection can be switched off, from a halfway screen position during programming. Patio furniture and a fouled side channel are the common triggers.
Which remote suits an outdoor screen installation?
The Telis 4 RTS patio remote is built for outdoor use and gives four channels on the same 433.420 MHz band the motor listens on. Somfy publishes 12 channels and a 656.2 foot open field range for the 525A2, and adding a sun or wind sensor to that network gives the screen an automatic retract.
Shade Motors Direct is an authorized source for genuine Somfy motorized window shade, blind, and drapery parts.
