S45 Roller Blind Tubes: Light vs STD vs HD & Compatible Motors

Acmeda S45 is one of the most useful tube families to identify when retrofitting an existing roller blind. It is common in Australian-made blinds and appears in Light, Standard and Heavy Duty versions. The three versions are related, but they are not identical in outside diameter or intended load.

What is an S45 roller blind tube?

S45 is an Acmeda roller blind tube family with a shaped internal profile designed to accept matching roller blind hardware. When the profile is confirmed, an existing S45 blind can generally be motorised without replacing the tube: the chain mechanism is removed and a compatible tubular motor is installed with the correct S45 crown and drive.

S45 Light

S45 Light has an outside diameter of about 43mm. It is the lighter member of the family and is normally found on smaller blinds. As a general guide, it is commonly used on blinds up to around 2.0 metres wide, depending on fabric weight and drop.

S45 Standard

S45 Standard measures about 44mm outside diameter and is one of the most common modern roller blind tubes. It offers more rigidity than the light version and is commonly used on everyday residential blinds up to roughly 2.4 metres wide, subject to the fabric and drop.

S45 Heavy Duty

S45 Heavy Duty has a substantially thicker construction and an outside diameter around 49mm. It is used where greater tube stiffness is needed, including wider blinds and heavier fabrics. Typical use can extend to around 3.0 metres, but blind design and fabric load still matter.

Do the same motors fit all three S45 versions?

The important point is not to choose from a generic list of 45mm motors. Use a motor and adaptor configuration that has been confirmed for the S45 profile and is appropriate for the blind load. Motor body size, crown and drive configuration and torque all matter.

See the current confirmed S45 motor options for the motors currently matched to this tube family, including rechargeable and hardwired choices where suitable.

Rechargeable or 240V for an S45 retrofit?

Rechargeable motors are popular for residential retrofits because no mains wiring is required at the blind. Hardwired 240V motors can make sense where fixed power is available, usage is high or the blind requires a different torque solution. Any mains electrical connection should be completed by a licensed electrician.

Torque does not fix a weak tube

More motor torque gives more lifting capacity; it does not make the roller tube stiffer. This matters on wider blinds. S45 Light, Standard and Heavy Duty exist partly because tube rigidity changes with construction, so the whole system needs to be considered rather than selecting the strongest motor available.

Not sure whether your tube is S45?

Do not rely on the outside measurement alone. Remove the idler, inspect the internal profile and compare it with our tube identification guide. L45 and other tubes can sit in the same general diameter range while needing completely different adaptors.

Once S45 is confirmed, the retrofit is straightforward in principle: choose a confirmed motor, use the correct crown and drive, fit the motor in place of the chain control, reinstall the blind and program direction and limits.