Buyer Question 01
How do I choose the right torque for a roller shutter motor?
Torque is the first technical decision in a shutter motor RFQ. If it is too low, the shutter may stall. If it is oversized, cost, noise and installation fit can suffer.
The buyer decision
A professional buyer should not ask only for “a 45mm shutter motor.” The correct request includes shutter width, height, curtain weight, tube diameter, slat material, operating frequency and installation environment. The supplier can then recommend torque with a practical margin instead of guessing from a model list.
Information needed before torque selection
- Shutter type: residential window shutter, shopfront shutter, garage shutter or commercial rolling door.
- Tube diameter and tube profile, especially when replacing an existing motor.
- Curtain weight or slat material, including aluminum, steel or insulated profiles.
- Opening width, travel height and expected daily operation frequency.
- Control preference: switch, RF receiver, electronic limit, smart control or manual override.
Common torque mistakes
| Mistake | Why it matters | Buyer action |
|---|---|---|
| Choosing only by maximum Nm | Oversizing may increase cost and may not fit smaller tubes. | Ask for a recommended torque range, not only the largest motor. |
| Ignoring tube diameter | The same curtain load can need different motor choices depending on tube size. | Provide tube drawings or photos with measurements. |
| No safety margin | Wind, friction and site variance can increase required load. | Ask the supplier to state the margin used in selection. |
RFQ checklist for torque selection
To receive a usable recommendation, send shutter type, tube diameter, curtain weight, opening width, travel height, destination voltage, control method, manual override requirement, quantity and target market. Photos or drawings reduce back-and-forth and help avoid a wrong sample.
Practical buyer scenario
A shutter company is motorizing a shopfront shutter with a heavy curtain, a 70 mm tube and daily operation. Walter should not recommend a motor only from width; the buyer should send curtain weight, tube diameter, travel height and use frequency so the torque margin is realistic.
Key procurement checks for torque selection
| Check | Why it matters | What to confirm |
|---|---|---|
| Curtain weight | Main load input | Send actual curtain weight or slat weight per square meter |
| Tube diameter | Changes load and accessory fit | Send tube OD, ID and profile photo |
| Travel height | Affects run time and limit setting | Send clear opening height |
| Use frequency | Affects duty and reliability | Residential, shopfront or commercial use |
Common mistakes to avoid
- Choosing torque only by shutter width
- ignoring tube diameter and crown or drive wheel fit
- using one torque for different slat materials
- leaving no safety margin for friction
- approving samples without testing under load
What to send to Walter
- Application and shutter type
- Tube diameter, curtain weight, width and travel height
- Voltage, control method and manual override need
- Accessory, certification, packaging and OEM requirements
- Quantity, target market and sample schedule
Related Walter motor pages
FAQ
What should I send before asking for price?
Send application, tube size, curtain weight or slat data, travel height, voltage, control method, accessories, quantity and target market.
Can Walter recommend a model from photos?
Photos help a lot, especially for tube, bracket and accessory matching. For final approval, drawings or samples are better.
Should this be confirmed before samples?
Yes. Confirming these details before samples reduces wrong model selection, rework and after-sales support problems.