Find a current motor to replace an old one by body diameter and torque

When a shutter or awning motor fails after years of service, the original model is often no longer sold, and the label may be unreadable. A replacement does not have to come from the same maker, but it has to match the old motor on a short list of points. Retrofitting a manual shutter or blind with a motor follows the same checklist, starting from the tube instead of the old motor.

What has to match

• Body diameter. The new motor must fit the same roller tube. Measure the tube's outer diameter and profile (round, octagonal or grooved); the selector on this page keeps the motor body at least 5 mm smaller than the tube's outer diameter. Almost all of the motors listed here are 35 mm, 45 mm or 58 to 59 mm.
• Torque. Match or slightly exceed the old motor's torque. If the label is lost, estimate it: required torque in Nm ≈ curtain weight in kg × 9.81 × tube radius in metres × 2. The selector on this page uses that rule of thumb; confirm the result with the new motor maker's sizing table.
• Speed. A much faster motor changes how the shutter behaves at the end positions and may strain the curtain. Stay close to the old speed.
• Crown and drive adapter. These parts transfer torque from the motor to the tube. They are specific to the motor series and the tube profile; check that adapters exist for your tube before ordering.
• Head and bracket. The motor head must fit the existing bracket or a bracket must be available that fits the shutter box or side plate.
• Length. The motor must fit inside the tube with room for the idler end.
• Limit setting. A mechanical-limit motor can be replaced by an electronic-limit one if it fits the same tube and bracket; either way, the end positions have to be set again.
• Control. A wired motor with up and down leads can usually be replaced by a wired motor with the same supply and the same wiring scheme. A radio motor needs a compatible remote or must be paired with a new one.

Retrofit: from manual to motorised

For a manual shutter with a strap or crank, motorising means replacing the tube's idler and drive end with a tubular motor, or fitting a strap-winder motor where the box cannot be opened. Check whether mains power is available at the window. If not, battery and solar motors avoid new wiring.

What the catalog shows

This page lists the motors you can actually compare against an old one: the tubular, roller shutter and awning motors whose manufacturer publishes both the torque and the body diameter.

• Body diameters: 45 mm is the largest group, followed by 35 mm and the 58 to 59 mm class, with a few 25 mm motors.
• Published torque runs from 0.7 Nm to 140 Nm, with a median of 20 Nm. About one in seven is rated 6 Nm or less and fewer than one in ten exceeds 80 Nm.
• Published output speeds have a median of 16 rpm.
• Almost all are mains AC motors (724 of 759). Mechanical limit setting is listed more often than electronic.
• Wistar, Becker and Geiger have the most entries here.

Explicit "replaces model X" records from manufacturers are not yet available in this catalog, so the list does not name a successor for a given old model. Use the diameter and torque columns, and the product filter, to build a shortlist, then check adapters and brackets with the maker.

Before you order

• Photograph the old motor's label and head, and measure the tube.
• Note the supply and how the old motor was wired or paired.
• Check the crown and adapter part numbers for your tube profile.
• If the shutter will join a smart home system later, choose the protocol now. See smart home integration.

For sizing a new installation rather than a replacement, see roller shutters and awnings and zip screens. The full list of in-tube motors is on tubular motors. Drives for shutters and awnings fall under IEC 60335-2-97.

Data as of 2026-10-05.