Somfy Simu T8S DMI 280Nm 99-108mm Motor Fit and Specs

A 99-108mm barrel rules most tubular motors out before torque enters the conversation. Somfy builds the Simu T8S DMI 280Nm Diameter 99-108mm 120V Slim Head (2008769) for that tube class, and the reference code states it: T828/10 S DMI Ø99-108 120/60. Installers size the barrel first. Torque follows.

Tube diameter decides this motor

Somfy publishes four T8 drive classes across the 280 Nm range, and each one seats on a different barrel. This reference carries the 99-108mm designation, which puts it between the 94mm units and the 124mm units in the same family. The motor body measures 3.15 in across. The operator runs 27.95 in long inside a 5.12 in square envelope at the head.

Specifiers who order the 94mm sibling by mistake keep the torque and lose the drive fit. Measure the barrel inside diameter at the motor end before you release the order. A fabricator who supplies the curtain can give you the figure from the shop drawing.

Doors and grilles it drives

Somfy classes the T8S DMI under industrial and commercial closure and rolling shutter duty. 280 Nm at 10 rpm turns heavy steel curtains, perforated security grilles, insulated slat doors and wide service counters. The published duty rating runs 10 cycles per day, which places the motor on storefront closures, loading bays and car park gates that open and shut a handful of times in a shift rather than on a high-traffic automatic door.

Ten rpm sounds slow next to a shade motor. On a 110mm barrel it moves curtain at a pace that matches what a facility manager wants from a 300 lb steel door.

Verified specs for reference 2008769

Somfy prints 0 W standby on this operator. A bank of eight doors on one panel draws nothing between cycles, which keeps the standby load off a facility's energy calculation. The power class sits above 750 W on a single phase supply, so an electrician sizes the branch circuit for that draw and keeps the run short enough to hold the motor inside the 132 V ceiling Somfy publishes.

Temperature limits matter on an exterior closure. Somfy rates the operator from 41°F to 104°F running, with storage down to -4°F. A specifier working an unheated loading bay in a cold climate checks the winter low against that running figure before committing the barrel.

Manual override at the DMI head

DMI marks the manual override head, and that head is the reason a specifier picks this reference over the plain T8S. Somfy lists a chain hoist for T8S DMI motors (9019458) against the ref, with the chain supplied as a separate part (9019460). Somfy also lists the T8-S DMI eye and hex shaft (9018569) for crank operation.

Store staff raise the door by hand during an outage. On a fire exit route or a loading dock that has to clear a truck, a building owner treats that override as a code question rather than a convenience. Order the hoist or the shaft with the motor. Retrofitting the head later means pulling the operator out of the barrel.

Brackets, drives and side plates

The T8-S / T8-S DMI Operator Bracket (9018069) carries the slim head at the motor end. Somfy builds it for the T8-S head profile, so it mates with this reference and its DMI siblings without an adapter plate.

On the drive side, Somfy lists the T8 97mm Round Set for 200Nm to 280Nm (9001312) alongside the 94mm drive (9001297) and the 124mm set (9013824). Match the set to the barrel you measured. The matching idle insert sits at the far end: 9542009 for 97mm, 9542008 for 94mm, 9542012 for 124mm. Somfy rounds out the fitment with the T6-8-9 side wall plates (9017157 and 9017166 at 280x280, 9017158 and 9017168 at 330x330) and a vertical wall angle bracket (9017172) for plate mounting.

Wiring, control and safety brakes

Four wires leave the head: line, neutral, and a conductor for each direction. An electrician lands them on a 120V reversing switch, a key switch or a relay output from a door controller. Class I insulation means the motor needs a ground connection, so the installer bonds the head to the enclosure.

Commissioning goes faster with the Standard Motor Tester Cable, 4-Wire (9012116). A technician bumps the motor in both directions at the barrel before the curtain goes on the door.

Somfy lists six Simu safety brakes against this reference, rated 258, 404, 708, 1000, 1500 and 3000 Nm. The Simu Safety Brake 404Nm (2005627) suits a mid-weight curtain on this motor, and the Simu Safety Brake M10A 1000Nm (2005629) covers the heavier assemblies that 280 Nm will lift. A door engineer picks the brake from curtain weight and drum diameter, not from motor torque. Specify it with the operator on any closure where a spring or shaft failure would drop the curtain.

Frequently asked questions

What tube does the Simu T8S DMI 280Nm fit?

Somfy publishes reference 2008769 as the 99-108mm unit, and the ref code reads Ø99-108. The motor body measures 3.15 in across. Pair it with the 97mm round set (9001312) and the 97mm idle insert (9542009) on a barrel in that range, and measure the inside diameter at the motor end before ordering.

How does the DMI manual override work?

The DMI head accepts a chain hoist (9019458, chain 9019460 ordered apart) or an eye and hex shaft (9018569). Staff drive the barrel by hand through that head during a power cut. Order the hoist or shaft with the motor, since fitting it later means removing the operator from the barrel.

Does this motor need a safety brake?

Somfy lists six Simu brakes from 258 Nm to 3000 Nm against this reference. A door engineer sizes the brake from curtain weight and drum diameter. Any commercial closure where a shaft or spring failure would drop the curtain gets one, and the 404 Nm and 1000 Nm units cover most assemblies this motor drives.

Which control works with a 4-wire T8S DMI?

Four conductors give you line, neutral and one wire per direction, which lands on a 120V reversing switch, a key switch or a relay from a door controller. The motor carries no radio receiver, so an RTS remote will not operate it. Class I insulation calls for a ground at the head.

Buy the Simu T8S DMI 280Nm Diameter 99-108mm 120V Slim Head (2008769) with the T8-S / T8-S DMI operator bracket (9018069), the brake your door engineer specified and a 4-wire tester cable (9012116) for commissioning. Somfy backs the operator for five years.

Shade Motors Direct is an authorized source for genuine Somfy motorized window shade, blind, and drapery parts.