ST28 Li-ion RTS Motor

Product Description

With its built-in rechargeable lithium-ion battery, the wirefree ST28 Li-ion RTS Motor eliminates the need for wiring or an electrician. The battery features an LED low battery indicator with the option to charge via a removable cable or solar power. A built-in radio receiver allows wireless control in any room within a 65-foot radius of the motor. Motor operates with simple voice commands using TaHoma and Amazon Alexa or Google Home through IFTTT.

Product Specs

  • Nominal Torque: 1.1 Nm.
  • Nominal Speed: 20 rpm.
  • Adjustable Speed: From 10-28 by increments of 2 rpm.
  • Radio Protocol: RTS Radio Technology Somfy.
  • Radio Frequency: 433.42 MHz RTS Radio Technology Somfy.
  • Battery Type: 12V 2600 mAh. Built in Li-ion battery.
  • Low Battery Indicator: LED (on motor head).

ANSI/WCMA A100.1 Compliance

If clutch-operated roller shades are installed in an environment where it's possible that young children will be present, they should comply with ANSI/WCMA A100.1, the Standard for Safety of Window Coverings.

If the shades that you purchase need to comply with this standard, it is your responsibility to inform Draper and opt-in to receive compliant products at time of order.

Spring-Loaded Cord Tension Device

Compliant window shades will include:

  • Pre-installed spring-loaded chain tension device with bead chain threaded through it
  • Approved permanent warning label attached
  • Approved mechanical fasteners for the tension device included

If the tension device is not installed properly, or becomes unattached from the mounting surface, the shade will be rendered partially inoperable. If installed properly, the tension device will prevent the creation of a hazardous loop and will maintain tension on the bead chain. The tension device and label require tools to be removed.


The testing required by the WCMA for products to comply with safety standard A100.1 includes:

  • UV stability testing - AATCC Test Method 16 for UV Stability
  • Impact testing - ASTM D5420
  • Bead chain durability testing
  • Operation cycle testing - 3,000 cycles per the standard

Our spring loaded tension device passed the requirements of these tests.

WCMA compliant hangtag warning label

Supporting Documents

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Part Numbers

  • C047.333 - ST28 Li-Ion RTS Motor


Case Studies

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