AUTOTROL 100-0021A Synchronous Ac Motor Single Phase 3M-769 120V 1.5RPM

( Brand: Autotrol ), ( Manufacturer Part Number: 100-0021A ), ( Model: 3M-769 ), ( Part Type: Ac Motor ), ( Actual Rated Input Voltage: 120 V ), ( Current Type: Ac ), ( Ac Frequency Rating: 60 Hz ), ( Base Rpm: 1 1/2 Rpm ), ( Ac Motor Type: Synchronous ), ( Ac Phase: Single Phase )

Review AUTOTROL Synchronous Ac Motor 120v 1.5rpm Model 3m 769 Single Phase

The **Autotrol 100-0021A Synchronous AC Motor** is a precision-engineered, single-phase electric actuator designed for applications requiring ultra-slow, consistent rotational movement with exceptional reliability. Operating at a nominal voltage of **120V AC**, this motor delivers a remarkably steady **1.5 RPM (revolutions per minute)** ideal for applications where gradual, controlled motion is critical, such as in industrial automation, laboratory equipment, or specialized machinery where fine adjustments are necessary. With a **3-meter (9.8-foot) cable length**, it offers flexibility in installation, allowing for easy integration into systems where space or wiring constraints may otherwise pose challenges. The motor s **769 series designation** suggests a robust, high-quality build, featuring a durable enclosure and sealed components to ensure longevity and resistance to environmental factors like dust, moisture, and temperature fluctuations.

This synchronous motor operates on the principle of precise magnetic alignment, ensuring smooth, vibration-free rotation without the need for additional gear reduction mechanisms, which simplifies system design and reduces maintenance requirements. Its single-phase construction makes it compatible with standard electrical setups, while its low-speed output eliminates the need for complex speed controllers, making it a cost-effective solution for applications where high torque at minimal speed is required. Whether used in automated valves, slow-moving conveyors, or precision positioning systems, the **Autotrol 100-0021A** delivers consistent performance with minimal energy consumption, making it an efficient choice for both industrial and specialized applications. Built to withstand continuous operation, this motor exemplifies reliability, precision, and ease of integration, ensuring seamless functionality in demanding environments.

### **Pros and Cons of buying a Autotrol 100-0021A Synchronous AC Motor (120V, 1.5 RPM, 3m, 769 Single-Phase)**

1. **Precision Speed Control** Synchronous motors provide exact, consistent rotational speed (1.5 RPM in this case), which is ideal for applications requiring steady motion, such as timers, metering devices, or slow-motion systems.

2. **High Efficiency** Synchronous motors are generally more energy-efficient than induction motors at steady loads, reducing long-term operational costs.

3. **Low Maintenance** Since they lack a rotor winding (unlike induction motors), there is no slip, reducing wear and tear, and extending the motor s lifespan.

4. **Quiet Operation** These motors typically run more smoothly and quietly compared to asynchronous (induction) motors, making them suitable for sensitive environments.

5. **Compact Design** The 3-meter lead length (769) suggests a compact, integrated solution, which can save space in installations.

6. **Single-Phase Compatibility** Works directly on standard 120V single-phase power, eliminating the need for additional wiring or phase conversion.

7. **Reliability for Low-Speed Applications** The slow speed (1.5 RPM) is well-suited for applications like clock mechanisms, slow conveyors, or precision indexing systems where high RPM would be impractical.

1. **Higher Initial Cost** Synchronous motors are generally more expensive upfront compared to induction motors of similar power ratings.

2. **Limited Speed Adjustability** The speed is fixed at 1.5 RPM (determined by the motor s design and power supply frequency). If variable speed is needed, additional gearing or external controllers may be required.

3. **Starting Requirements** Synchronous motors often require assistance (e.g., a starter motor or external power source) to align the rotor with the magnetic field during startup. This can add complexity to the system.

4. **Sensitivity to Load Variations** If the load exceeds the motor s capacity, it may stall or lose synchronization, potentially causing damage if not properly protected.

5. **Specialized Applications** Not as versatile as induction motors, which can handle a wider range of speeds and loads without additional modifications.

6. **Potential for Resonance Issues** At very low speeds (like 1.5 RPM), mechanical resonance or vibration could become a concern if the system is not properly balanced or damped.

7. **Limited Availability of Spare Parts** Due to niche use cases, finding replacement parts or technical support may be more difficult than for common induction motors.

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The **Autotrol 100-0021A synchronous AC motor** is an excellent choice for applications requiring **extremely precise, low-speed, single-phase operation** with minimal maintenance. Its efficiency, quietness, and reliability make it ideal for specialized uses such as timing devices, metering systems, or slow-motion automation. However, its **higher cost, fixed speed, and dependency on proper starting conditions** may not justify its use in applications where flexibility or variable speed is required.

If your application demands **steady, slow rotation with minimal vibration and long-term reliability**, this motor is a strong recommendation. If, however, you need **adjustable speed, higher torque at startup, or cost efficiency**, an induction motor with a gearbox or a variable frequency drive (VFD) might be a better alternative.

- You need a **fixed, ultra-low-speed (1.5 RPM) solution** for a single-phase 120V system.

- Your application benefits from **high precision, low maintenance, and quiet operation**.

- The motor s compact design (with 3m lead) fits your installation constraints.

- You can accommodate the **higher upfront cost** for long-term reliability.

- You require **variable speed control** (e.g., a gearmotor with a VFD or a stepper motor).

- Your application involves **high starting torque or frequent load changes**.

- Cost efficiency is a priority, and an induction motor with a gear reduction might suffice.

For most general industrial or automation applications, a **geared induction motor with a VFD** would offer more flexibility. However, for niche, precision-driven uses, the **Autotrol 100-0021A is a well-suited, high-performance option**. Always verify compatibility with your specific load requirements before purchasing.

Details:

Autotrol Synchronous AC Motor 120V 1.5RPM model 3M 769 Single Phase.

part #: 1000021a price

• $71.24

specifications oelemot:

• brand: Autotrol
• mpn: 100-0021a
• model: 3m-769
• part type: Ac Motor
• actual rated input voltage: 120 V
• current type: Ac
• ac frequency rating: 60 Hz
• base rpm: 1 1/2 Rpm
• ac motor type: Synchronous
• ac phase: Single Phase

seller oelemot:

• rating: 0.0%
• city: Chico, California
• # reviews: 0

general oelemot:

• condition: Used
• Industrial Automation Motion Controls > Electric Motors > General Purpose Motors

shipping oelemot:

• cost: $70.49
• carrier: USPS
• class: Standard
• transit: 6-9 Days
• service: USPS Ground Advantage
• type: Calculated

payments oelemot:

• credit card: Visa
• other
• wallet: Paypal

returns oelemot:

• policy: No Returns

offer oelemot:

• availability: In Stock
• started: March 19, 2026
• options: Ship-to-home
• sold: 0
• quantity: 1
• best offers: True

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