Tube inner diameter settles this motor before torque does. The Somfy Sonesse 40 WT 404S2 needs a roller tube with at least 38 mm of clear inner diameter, and Somfy prints that minimum as a requirement in the 400 Series databook. Measure the inside of the tube, then order.
Tube fit comes first on the 40 mm platform
Somfy builds the 404S2 on the 40 mm motor platform, so the body slides inside a 1.5 inch or larger roller tube. That 38 mm inner diameter minimum keeps the tube wall off the motor shell. A tube that pinches the body carries motor sound straight into the fabric and loads the gearbox for no reason. Interior aluminum tubes at 1.57 inch outer diameter clear it without argument. Thin-wall 1.5 inch extrusions sit close, and a caliper on the inside wall answers it in one reading.
Somfy lists this reference for interior window coverings, interior blinds, and projection screens. Keep it indoors. The IP 44 rating covers splash and dust in a conditioned room, and Somfy's weather-rated ranges carry exterior duty.
Shades the 404S2 lifts well
4 Nm at 36 rpm puts the 404S2 in the middle of interior roller and solar shade work. The speed matters as much as the torque here. 36 rpm turns a bare 1.5 inch tube at about 2.8 inches of fabric per second, and the rate climbs as the roll builds diameter. That reads as controlled on a tall drop rather than abrupt. Projection screen builders pick this band for the same reason.
Fabric weight, roll build-up, and drop all feed the torque math. Somfy's 400 Series databook carries the lift tables that turn a shade size into a torque number, and the 404S2 sits at the entry of the four-newton-metre band. Heavier blackout fabric on a wide opening pushes you up the range to the 406A2 or across to the 50 mm platform.
Verified specs
| Somfy reference | 1240377 |
| Somfy product name | Sonesse 40 WT 404S2 RH with Fast Connector |
| Torque | 4 Nm (35 in-lb) |
| Speed | 36 rpm |
| Power supply | 120 V AC, 60 Hz |
| Rated current | 0.95 A |
| Power in operation | 110 W |
| Standby consumption | 0.46 W |
| Noise level | 42 dB |
| Protection rating | IP 44, interior use |
| Insulation class | Class I |
| Limit switch | Progressive Adjustment (PA), 40 turns |
| Minimum tube inner diameter | 38 mm |
| Cable | Fast Connector pigtail, 0.5 m (1.6 ft) |
| Control | Wired, four conductor |
| Approval | UR |
| Warranty | 5 years |
Figures come from Somfy's published data for reference 1240377 and the Somfy 400 Series databook.
Crowns, drives and tubes that fit
The motor needs a crown at the head end and a drive wheel that keys into the tube. Somfy lists the 40 mm round set as 9012224 and the octagonal set as 9012225, and the store stocks both patterns plus the rubberized versions that damp tube rattle.
Pick the set by tube profile. A cylindrical aluminum tube takes the Somfy LS40 Crown and Drive Set (9012224), or the rubberized LS40 crown and drive set (9016654) when the install sits near a bedroom wall and every decibel counts. Octagonal steel tube takes the LS40 octagonal rubberized crown and drive set (9016655). If you are cutting tube for the job, the Somfy 40 mm octagonal tube (1781154) ships by the foot in 20 foot lengths and pairs with the octagonal drive.
Use 40 mm crowns and drives on this motor. Parts cut for the 50 mm platform will not seat, and a drive that almost fits will chew its keyway inside a season.
The Fast Connector changes your rough-in, and PA sets your travel
WT marks this as Somfy's wired four-conductor control, with no radio inside the head. The Fast Connector variant ends in a 0.5 m pigtail with a keyed plug instead of a long tail of loose conductors. An electrician lands the mating half in the junction box during rough-in, the shade installer plugs the motor in at hang, and nobody strips a conductor on a ladder.
Plan the box inside 18 inches of the motor head. 0.5 m of pigtail disappears fast once the motor sits in a pocket and the connector needs slack to swing. Longer runs happen on the building side of the plug, in conduit, where an inspector can see them. The 0.46 W standby draw means a bank of twelve motors idles at under 6 W, which keeps the circuit math simple on a commercial floor.
Progressive Adjustment gives the installer 40 turns of tube rotation between the two limits. 40 turns on a 1.5 inch tube covers a drop past 14 feet before build-up, so interior work rarely runs out of travel. Set the limits with the fabric on the tube and the hembar in its finished position, because the roll diameter grows as fabric wraps and a limit set on bare tube drifts.
Somfy's 400 Series databook carries the limit procedure for the PA head, and the Somfy Pro product page for 1240377 carries the current data sheet. Read the head markings on the motor you receive before you set anything, since Somfy ships the 404S2 in round head and star head patterns across the 400 Series.
Ordering the 404S2
The Somfy Sonesse 40 404S2 WT 120V motor with Fast Connector (1240377) suits an interior roller shade or a projection screen on a 1.5 inch tube with a wired switch or a Somfy motor controller driving it. Order the crown and drive set in the same cart, match it to your tube profile, and the motor arrives ready to hang.
Sonesse 40 WT 404S2 questions
What tube does the Sonesse 40 404S2 fit?
Any roller tube with a clear inner diameter of 38 mm or more. That covers 1.5 inch and 1.57 inch aluminum extrusions and 40 mm octagonal steel tube. Measure the inside wall rather than the outer diameter, because wall thickness varies between extrusions and a thick-wall 1.5 inch tube can fall under the minimum.
How does the Fast Connector differ from the standard cable?
The Fast Connector version carries a 0.5 m pigtail that ends in a keyed plug. Reference 1001553 carries the same 404S2 motor with a 2 m cable of loose conductors instead. Pick the Fast Connector when an electrician rough-ins the box before the shades arrive, and keep the box within 18 inches of the head.
Does this motor work with a Somfy remote?
Not on its own. The 404S2 WT is a wired motor with no radio receiver inside it, so a wall switch or a Somfy motor controller drives it. Adding a Somfy radio receiver between the supply and the motor brings remote, app, and voice control to a wired head.
Which crown and drive set should I order with it?
Match the tube. Round aluminum tube takes the 9012224 set or the rubberized 9016654. Octagonal tube takes the 9016655 rubberized octagonal set. Rubberized crowns and drives cut tube rattle on a hard ceiling pocket, and they cost a few dollars more per shade.
Shade Motors Direct is an authorized source for genuine Somfy motorized window shade, blind, and drapery parts.
