Question: This motor worked one week after installtion, after that it got struck and not moving smothly. We put another motor then it working
S4A:We are glad to hear that the automatic door system is currently running smoothly with the new replacement motor.
Regarding the first motor which "worked for one week, then got struck and moved un-smoothly,"
our engineering team has conducted a comprehensive internal technical analysis. In the automatic door industry,
when a motor encounters this specific symptom shortly after installation, it is usually triggered by one of the following factors.
We highly recommend having your technicians double-check the onsite environment to safeguard the new motor:
1. Over-Tensioned Drive Belt (Most Common Cause)
If the timing belt is adjusted too tightly during installation, it exerts an excessive radial force on the motor's output shaft.
Within a week of operation, this extreme tension can cause the internal bearings of the motor to wear down prematurely
or deform due to friction heat, eventually leading to the motor getting stuck or losing its smoothness.
2. Mechanical Track Resistance & Overload
If the door panels exceed the rated weight capacity, or if the guide rails/hangers are not perfectly aligned,
the rolling resistance will significantly multiply over a few days. Running under a constant overload condition
forces the motor to overheat, causing the internal gearbox lubricants to dry up or the gears to seize.
3. Frequent Motor Stalling (Improper Stopper Settings)
If the mechanical end-stoppers (limits) are positioned incorrectly, the door might constantly smash or push hard
against the boundaries before the controller cuts the power. This continuous "stalling status" creates high currents that
can damage the internal gear structure within days.
Our Next Steps & Support:
Onsite Inspection Suggestion: Please ask your team to verify that the belt tension is optimal (not too rigid) and ensure
the door leaf can slide seamlessly by hand when the power is turned off.
Warranty Solution: At S4A, we strictly stand behind our commitment to "Quality First". We want to fully investigate the
defective unit to improve our quality. Could you please keep the stuck motor aside? We will gladly send you a technical
credit or issue a formal replacement item in your next shipment.

Thank you for your long-term trust and partnership. Please let us know if there is anything else we can assist you with!
Update: 6th,July,2026
Again, S4A deeply appreciates your efforts and looks forward to more opportunities to work with you. If need our support, pls contact as below:
S4A INDUSTRIAL CO.,LIMITED
Contact Sales: Ms Anna Zhang
Tel:+86 755 29450011 EXT: 608
Mob/whatsapp/Viber +86 134 10500721
Email: sales1@s4a-access.com
Factory Address:Building S4A, South Third Lane, Qiuyuling Street, Zhangkeng Village, Hengli Town, Dongguan City, Guangdong Province Office Address:#601,floor 6 ,building 1,JINFANGHUA industrial zone, Bantian St. Longgang Dist. Shenzhen, PRC.
Wenn Sie an unseren Produkten interessiert sind und weitere Informationen wünschen, hinterlassen Sie bitte hier eine Nachricht. Wir werden Ihnen so schnell wie möglich antworten.