A 6 Nm motor rated at 38 dB gives you a wide interior roller shade in a room where sound carries. The Somfy Sonesse ULTRA 506A2 RS485 holds that rating and reports its position back over a wired bus. Tube diameter settles the fit before anything else. Somfy publishes a 1.85 in minimum internal tube diameter for this motor, which puts a 2 in LT50 tube at the bottom of its working range and a 2.5 in tube in comfortable territory.
Shades this motor suits
Somfy lists two applications for the 506A2 RS485: interior window coverings and projection screens. The 6 Nm rating at 24 rpm covers the fabric weight of a large interior roller in a conference room, a lobby, or an auditorium. Projection screen work leans on the same pair of numbers, since a screen carries a heavy bottom bar and asks for a repeatable stop position every time.
The RS485 line is what separates this motor from the RTS version sitting beside it in the Sonesse ULTRA family. A radio motor takes commands. This one takes commands and answers, so a building controller reads the real position of every shade on the bus rather than assuming it. Specifiers building a facade of forty shades value that answer, because an out-of-sync shade shows up in software instead of on a walkthrough.
Somfy engineered the ULTRA platform around sound. At 38 dB the motor runs below the background level of most occupied rooms, which is the reason the ULTRA line keeps winning boardroom and hospitality specifications. Buy the Sonesse ULTRA 506A2 RS485 motor when the room demands a quiet raise and the control system demands feedback.
Tube diameter and the 1.85 inch floor
Somfy publishes a 1.85 in minimum internal tube diameter and a 1.97 in motor diameter for the 506A2 RS485. Read those two rows together. The motor body needs the bore, and the crown needs a seat inside the same tube. A 2 in tube with a thin wall clears it. A 1.75 in tube does not, and no crown solves that.
Motor length runs 33.58 in. Add the head, the bracket, and the idler at the far end before you cut fabric. On a 48 in shade the motor fills most of the tube. The tube carries that load with no trouble, and the number is worth knowing before the fabric width gets locked in.
The head is a star. A star bracket holds it, and a round or CMO bracket does not. Ordering a bracket family that matches the head is the single fitment error that sends a motor back, so confirm the head style against the bracket on the drawing.
Verified specifications
| Specification | Published value |
|---|---|
| Torque | 6 Nm (53 in-lb) |
| Speed | 24 rpm |
| Noise level | 38 dB |
| Control | RS485, Somfy Digital Network |
| Power supply | 120V AC, 60 Hz, 108-132 V |
| Operating current | 0.95 A |
| Operating power | 114 W |
| Standby power | 0.5 W |
| Protection index | IP 31 |
| Protection class | Class I |
| Head type | Star |
| Limit switch | Electronic, 250 turn capacity |
| Minimum tube internal diameter | 1.85 in |
| Motor diameter | 1.97 in |
| Motor length | 33.58 in |
| Cable | SJTW, 9.84 ft, white |
| Operating temperature | 32 to 140 °F |
| Storage temperature | -4 to 176 °F |
| Thermal protection | 4 min |
| Weight | 8.51 lb |
| Applications | Interior shades, projection screens |
| Warranty | 5 years |
Figures come from Somfy's published record for reference 1002566 on somfypro.com and somfysystems.com.
Crown and drive sets for the LT50 tube
The crown centers the motor body in the tube and the drive transmits torque to the tube wall. Pick the pair that matches your tube profile, not the pair that matches the motor, since every LT50 motor takes the same crown seat.
For a 70mm octagonal tube, the Octagonal LT50 70mm Crown and Drive Set (9012234) seats the motor and locks the drive into the octagonal flats. Round aluminum tube takes a clip drive instead, sized to the tube inside diameter.
Mounting at the head end runs through the LT50 Universal Bracket with Spring Clip (9420631). The spring clip holds the star head captive once the motor drops in, which means one installer can set a long tube without a second pair of hands on the ladder.
SDN wiring and two-way control
The 506A2 RS485 runs on 120V AC and carries an RS485 data pair for control. Power and data travel on separate paths, and each motor holds an address on the bus. Somfy's animeo IP and SDN controllers read those addresses, so a floor of shades answers a single scene command and reports back when it lands.
Standby draw sits at 0.5 W. On a 60 motor install that adds 30 W of idle load, a figure worth handing to the electrical engineer during coordination rather than after energization.
Cable length out of the motor is 9.84 ft of SJTW. Plan the junction box within that reach or budget a listed splice. Class I protection means the motor needs a ground conductor, and IP 31 keeps it indoors.
Commissioning and limit setting
Limits on this motor are electronic with a 250 turn capacity, which covers tall shades without a mechanical stop. Setting them needs a tool that speaks RS485.
The RS485 Setting Tool (9017142) reads motor addresses and sets limits at the shade, which suits a lift where you want the motor commissioned before the ceiling closes. For bench work or a laptop-driven commissioning session, the USB to RS485 Adaptor (9015260) puts the bus in front of Somfy's software so you address a run of motors in one pass.
Order the tool with the first motor on a project. Crews that wait until install day tend to lose an afternoon to a shipping window. Put the motor, the crown and drive set, the bracket, and one commissioning tool on the same purchase order, and the shade lands on the drawing the day it goes up.
Frequently asked questions
What tube does the Sonesse ULTRA 506A2 RS485 fit?
Somfy publishes a 1.85 in minimum internal tube diameter, with a 1.97 in motor diameter. A 2 in LT50 tube works, and a 2.5 in tube gives more clearance. Match the crown and drive to the tube profile, octagonal or round, since the motor takes the same crown seat across the LT50 range.
How loud is this motor?
Somfy rates the Sonesse ULTRA 506A2 RS485 at 38 dB, one of the quietest figures Somfy publishes for a wired AC tubular motor. That level keeps the raise below normal conversation in a boardroom or a hotel suite.
Which bracket holds a star head motor?
A star head needs a star bracket. The LT50 Universal Bracket with Spring Clip (9420631) accepts it and holds the head captive during install. A round head or CMO bracket will not retain this motor, so confirm the head style before ordering hardware.
Does this motor work with RTS remotes?
No. The 506A2 RS485 carries no radio receiver. Control arrives over the RS485 bus from an SDN or animeo IP controller. Somfy builds an RTS version of the Sonesse ULTRA 50 for radio projects, and that motor takes Situo and Telis transmitters.
Shade Motors Direct is an authorized source for genuine Somfy motorized window shade, blind, and drapery parts.
