Overview
A starting auto transformer is a type of transformer used to start electric motors by providing a reduced voltage to the motor at the start, reducing the inrush current. Once the motor reaches a specific speed, the full voltage is applied to the motor.
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Technical Parameters
Starting Auto Transformer Technical Parameters
| Model | Power (KW) | A | B | C | E | F | G |
|---|---|---|---|---|---|---|---|
| QZB-14 | 14 | 310 | 135 | 240 | 210 | 100 | |
| QZB-17 | 17 | 310 | 140 | 240 | 210 | 100 | |
| QZB-22 | 22 | 310 | 145 | 250 | 210 | 105 | |
| QZB-30 | 30 | 320 | 150 | 250 | 210 | 105 | |
| QZB-40 | 40 | 330 | 150 | 265 | 210 | 110 | |
| QZB-45 | 45 | 330 | 153 | 265 | 210 | 113 | |
| QZB-55 | 55 | 370 | 170 | 280 | 220 | 125 | |
| QZB-75 | 75 | 370 | 170 | 280 | 220 | 130 | |
| QZB-90 | 90 | 395 | 195 | 320 | 280 | 150 | |
| QZB-100 | 100 | 395 | 200 | 320 | 280 | 150 | |
| QZB-115 | 115 | 395 | 205 | 320 | 280 | 155 | |
| QZB-135 | 135 | 395 | 205 | 350 | 280 | 155 | |
| QZB-160 | 160 | 445 | 185 | 375 | 280 | 145 | |
| QZB-190 | 190 | 470 | 185 | 420 | 280 | 145 | 17.5 |
| QZB-225 | 225 | 520 | 185 | 420 | 280 | 150 | 21.5 |
| QZB-260 | 260 | 520 | 190 | 460 | 320 | 150 | 21.5 |
| QZB-300 | 300 | 560 | 195 | 460 | 320 | 155 | 21.5 |
- Dimensions in the table refer to the left schematic diagram.
- Product dimensions are for reference only. Custom designs and specifications for motor autotransformer starters, motor step-down autotransformer starters, and three-phase autotransformer starters can be made based on customer requirements.
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Product Feature
Starting auto transformers are widely used in applications where a high starting torque is needed, but a controlled, reduced starting current is desired. Auto transformers are more energy-efficient compared to other types of starting transformers because they use a portion of the transformer windings for starting, and then switch to normal operation. This allows for a smoother start and reduces mechanical stresses on the motor.
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In response to fierce market competition and to meet customer demands, our company adheres to a market-oriented approach and a customer-centric philosophy. We have earned widespread recognition from our clients through efficient, comprehensive services and superior product quality.
Our Commitments
- Product Lifespan Guarantee: The operational lifespan of our transformers is no less than 30 years.
- Strict Quality Control:
- Upon receiving bid documents, we promptly initiate the evaluation process to ensure all customer requirements are fully addressed.
- We carefully select certified suppliers and strictly follow quality management standards to control and inspect raw materials and components.
- We produce high-quality, customer-satisfactory parts in full compliance with contract and technical agreement requirements.
- After-Sales Service Commitment:
- All performance indicators and technical specifications of our transformers meet or exceed national standards.
- Within 3 years of installation and commissioning, if any oil leakage occurs due to manufacturing defects in oil-immersed transformers, we will repair it at no cost.
- For any critical component defects identified during production or issues discovered during installation, we prioritize resolution to meet project timelines, followed by thorough responsibility analysis and necessary repairs or replacements.
- We welcome customers to supervise the manufacturing process at our facility and will provide full support.
After-Sales Support
We offer comprehensive after-sales services, including free guidance for installation and commissioning. After the product is operational, if the customer requires support, our service team will respond promptly:
- Arrival on-site within 24 hours for locations within 300 km.
- Arrival on-site within 48 hours for locations beyond 300 km.
Additionally, we have established a robust regular follow-up system. We conduct periodic written or on-site visits to monitor the performance of in-service products, ensuring our customers have continuous peace of mind.
International Service Methods
Remote Technical Assistance
Our service team provides 24/7 online technical support, including video calls, troubleshooting guides, and documentation, ensuring immediate assistance regardless of time zones.
Detailed remote diagnostics can be conducted using customer-provided data or live visual inspections.
On-Site Support
For complex issues, we dispatch experienced technicians to the customer site promptly, adhering to the agreed international response timelines.
On-site services include installation guidance, commissioning, maintenance, and repairs.
Dedicated Service Representatives
Each international client is assigned a dedicated service representative to coordinate all aspects of after-sales support, including issue resolution and regular follow-ups.
Local Service Partnerships
We collaborate with certified local service partners in key markets to ensure faster response times and efficient support. These partners are fully trained in our products and processes to uphold our quality standards.
Regular Follow-Up Visits
Post-installation, we perform scheduled follow-up visits, either in person or virtually, to monitor product performance and address customer feedback. This proactive approach ensures optimal operation and customer satisfaction.
Why This Matters
Our comprehensive international service system combines swift response, advanced technical support, and localized expertise to provide our global clients with reliable and professional after-sales services. We are committed to building lasting partnerships through consistent support and excellence.
FAQs
When purchasing an Starting Auto Transformer, you may want to know the following questions & answers.
1. What is the voltage rating for the starting auto transformer?
The voltage rating of a starting autotransformer is typically determined by the motor’s operating voltage and the desired starting voltage reduction. Autotransformers are designed to reduce the starting voltage supplied to the motor, and the reduction factor depends on the configuration and application.
Key Points for Voltage Rating:
Motor Operating Voltage: The autotransformer’s voltage rating should match the motor’s nominal operating voltage. Common motor voltages are:
- 230V
- 400V
- 460V
- 690V
- 11kV (for high-voltage motors)
Voltage Reduction: When using an autotransformer for motor starting, the voltage supplied to the motor is typically reduced to a percentage of the full voltage. The most common reductions are:
- 50% of the motor’s full voltage (if a 2:1 reduction ratio is used).
- 65% to 80% of the motor’s full voltage (more typical in practice).
For instance:
- If the motor’s nominal voltage is 400V, and the autotransformer provides 65% of the full voltage, the motor will receive 260V during starting.
Autotransformer Voltage Rating: The autotransformer’s voltage rating is usually chosen to match the full motor voltage (i.e., the motor’s rated line voltage) since it is connected in parallel with the supply during starting.
- For a 400V motor, a 400V autotransformer would typically be used.
- For a 690V motor, a 690V autotransformer would be required.
High Voltage Motors: For motors that operate at higher voltages (such as 6.6kV or 11kV), the autotransformer will also need to be rated for that voltage level. The design will depend on the voltage reduction factor and the specific starting requirements.
Example Scenario:
- If you have a 400V motor and you are using an autotransformer to reduce the starting voltage by about 60%, the autotransformer should have a 400V voltage rating, even though the motor will only receive 240V initially during the start.
In summary, the autotransformer voltage rating should match the full-rated voltage of the motor, while the actual starting voltage applied to the motor will be a lower percentage of that value.
2. What is the current capacity (in amps) of the starting auto transformer?
The capacity of a starting autotransformer (AT) in terms of amps depends on several factors, such as the motor rating (in horsepower or kilowatts), the voltage, and the autotransformer’s design. The starting autotransformer is typically used to reduce the voltage applied to the motor at start-up, thereby limiting the starting current.
To calculate the current capacity (in amps) of the autotransformer, you would typically:
Motor Full Load Current (FLC): Find the full load current of the motor (in amps) based on its rating.
- For example, a 10 HP motor operating at 400V typically has a full load current of around 15-18 amps.
Autotransformer Ratio: An autotransformer usually applies a reduced voltage to the motor (often 65-80% of the full line voltage). This reduces the starting current.
- The current supplied to the motor by the autotransformer is usually about 1/3 of the motor’s full load current, depending on the voltage reduction ratio.
Autotransformer Current: The autotransformer itself should be rated to handle the current it supplies to the motor.
- For a 10 HP motor, if the starting current is reduced by a factor of about 3, the autotransformer would need to handle roughly 5-6 amps (based on 15-18 amps full load current).
The autotransformer’s current rating will depend on the specific motor’s full load current and the desired voltage reduction. You may want to consult the manufacturer’s specifications for precise values tailored to your motor and autotransformer setup.
3. What are the available power ratings (in kVA) for the starting auto transformer?
The available power ratings for a starting autotransformer typically range from small to large values, depending on the specific application and the motor being started. The power rating is directly related to the motor’s full-load current and the autotransformer’s ability to handle this current while reducing the starting voltage and torque.
Here’s a general breakdown of the power ratings in kVA for autotransformer starters:
1. Small Power Ratings (up to 100 kVA)
- Common range: 5 kVA – 100 kVA
- Applications: Used for smaller motors, such as those in HVAC systems, small pumps, fans, and conveyors.
2. Medium Power Ratings (100 kVA – 500 kVA)
- Common range: 100 kVA – 500 kVA
- Applications: Suitable for motors in industrial processes like larger pumps, compressors, conveyors, and other medium-sized machinery.
3. Large Power Ratings (500 kVA – 2500 kVA and above)
- Common range: 500 kVA – 2500 kVA
- Applications: For heavy industrial machinery, large motors in mills, crushers, large pumps, and crushers.
Key Considerations:
Power ratings of autotransformer starters are typically designed based on the starting current of the motor and the level of voltage reduction required. An autotransformer reduces the starting voltage to 60%, 50%, or 40% of the rated voltage, depending on the transformer’s configuration and the starting characteristics needed for the application.
Sizing the autotransformer: To determine the appropriate kVA rating of an autotransformer, it’s essential to know the motor’s full-load current, the voltage reduction factor (e.g., 50% voltage means the autotransformer is rated for 1.73 times the motor’s full-load current), and whether additional surge or transient protection is required.
Multiple Stages of Starting: Some systems may use a “multi-step” autotransformer with more than one tap for different levels of starting voltage reduction. This helps to handle large motors more efficiently and in stages.
In summary, the power ratings for autotransformer starters typically range from a few kVA (for smaller motors) up to 2500 kVA or more for large industrial motors. The key is matching the starter’s capacity to the motor’s specific requirements, ensuring safe, efficient operation during startup.
4. What is the starting method supported by the auto transformer (e.g., direct-on-line, star-delta)?
Yes, Auto Transformers are typically designed and manufactured to comply with a range of international standards, ensuring their safety, performance, and reliability across various applications. These standards cover aspects such as electrical safety, performance, environmental conditions, and more. The most commonly referenced standards for Auto Transformers are from organizations like IEC, UL, and CSA, among others.
1. IEC (International Electrotechnical Commission) Standards
The IEC provides a set of standards for electrical and electronic equipment, and Auto Transformers must meet the relevant ones. Some key IEC standards applicable to Auto Transformers include:
- IEC 60076-1: Power transformers — General rules. This standard provides general requirements for power transformers, including auto transformers, concerning their construction, testing, and operating conditions.
- IEC 60742: General rules for the design and construction of autotransformers. It specifically applies to autotransformers and outlines design guidelines for their safe operation.
- IEC 60076-3: Power transformers – Insulation levels, dielectric tests, and external clearances. For transformers, including auto transformers, this standard covers insulation requirements and tests that must be performed to ensure safe operation.
- IEC 60529: Degrees of protection provided by enclosures (IP Code). This standard defines the protection level for auto transformers against dust and water ingress.
- IEC 61000-4: Electromagnetic compatibility (EMC). It covers the testing of auto transformers to ensure that they do not interfere with other electronic systems and are resilient to electromagnetic disturbances.
2. UL (Underwriters Laboratories) Standards
UL is a safety certification organization that establishes widely adopted standards for electrical and electronic devices. For auto transformers, the relevant UL standards include:
- UL 506: Transformers for use in audio, video, and similar equipment. This standard applies to certain types of auto transformers used in specific audio, video, and similar applications.
- UL 1446: Systems of Insulated Wires and Cables. This standard specifies requirements for the wire and cable systems used in transformers, including auto transformers, and ensures that they meet fire safety and electrical insulation criteria.
- UL 1012: Power units other than class 2. This standard covers electrical power supply devices, including auto transformers used in applications outside of class 2 devices.
3. CSA (Canadian Standards Association) Standards
In Canada, CSA sets the standards for electrical equipment, including transformers. Auto transformers must comply with CSA standards, such as:
- CSA C22.2 No. 0: General Requirements – Canadian Electrical Code. This code applies to electrical devices, including transformers, and establishes general safety and performance criteria.
- CSA C22.2 No. 14: Industrial Control Equipment. This standard may apply if the auto transformer is part of an industrial control system.
- CSA C22.2 No. 66: Electric Transformers. This standard governs transformers, including auto transformers, and addresses key safety and operational aspects.
4. Other Relevant Standards
In addition to the IEC, UL, and CSA standards, auto transformers might also comply with other regional or specialized standards depending on the application or industry. Some of these include:
- NEMA (National Electrical Manufacturers Association) Standards: For auto transformers used in North America, NEMA standards like NEMA MG-1 for motors and NEMA ST-1 for transformers may apply.
- ISO 9001: Quality management systems – This international standard ensures that the manufacturer of the auto transformer follows high-quality production and testing practices.
- IEEE (Institute of Electrical and Electronics Engineers) Standards: In certain cases, IEEE standards for transformers and electrical safety may apply.
Key Compliance Areas for Auto Transformers
The main areas in which Auto Transformers need to comply with these international standards include:
- Safety: Ensuring protection against electrical hazards, such as overcurrent, overload, and short circuits, as well as providing safe insulation levels and clearances.
- Electromagnetic Compatibility (EMC): Compliance with standards to minimize electromagnetic interference (EMI) and prevent malfunctioning of nearby electronics.
- Thermal Performance: Compliance with temperature rise tests, ensuring the auto transformer can operate safely within its rated temperature limits.
- Insulation: Ensuring that the insulation materials meet the specified dielectric strength and thermal properties as outlined by the relevant standards.
- Environmental Protection: Standards for protection against dust, moisture, and other environmental factors, ensuring the transformer operates reliably in various conditions.
- Energy Efficiency: In some markets, transformers, including auto transformers, must meet energy efficiency standards to reduce losses and ensure sustainability.
Conclusion
An Auto Transformer is generally designed to meet internationally recognized standards such as IEC, UL, CSA, and others, ensuring compliance with safety, quality, and performance requirements. These standards are crucial for guaranteeing the reliability and safety of the transformer in various operational environments, from industrial applications to residential and commercial uses.
Manufacturers typically test their auto transformers to ensure that they meet these standards, and often provide certification marks from recognized organizations (e.g., UL listing, IEC compliance) as proof of conformity. Therefore, when purchasing or using an auto transformer, it is essential to verify that it carries the appropriate certification for your region and application to ensure compliance and safety.
5. Does the auto transformer comply with international standards (e.g., IEC, UL, CSA)?
Yes, Auto Transformers are typically designed and manufactured to comply with a range of international standards, ensuring their safety, performance, and reliability across various applications. These standards cover aspects such as electrical safety, performance, environmental conditions, and more. The most commonly referenced standards for Auto Transformers are from organizations like IEC, UL, and CSA, among others.
1. IEC (International Electrotechnical Commission) Standards
The IEC provides a set of standards for electrical and electronic equipment, and Auto Transformers must meet the relevant ones. Some key IEC standards applicable to Auto Transformers include:
- IEC 60076-1: Power transformers — General rules. This standard provides general requirements for power transformers, including auto transformers, concerning their construction, testing, and operating conditions.
- IEC 60742: General rules for the design and construction of autotransformers. It specifically applies to autotransformers and outlines design guidelines for their safe operation.
- IEC 60076-3: Power transformers – Insulation levels, dielectric tests, and external clearances. For transformers, including auto transformers, this standard covers insulation requirements and tests that must be performed to ensure safe operation.
- IEC 60529: Degrees of protection provided by enclosures (IP Code). This standard defines the protection level for auto transformers against dust and water ingress.
- IEC 61000-4: Electromagnetic compatibility (EMC). It covers the testing of auto transformers to ensure that they do not interfere with other electronic systems and are resilient to electromagnetic disturbances.
2. UL (Underwriters Laboratories) Standards
UL is a safety certification organization that establishes widely adopted standards for electrical and electronic devices. For auto transformers, the relevant UL standards include:
- UL 506: Transformers for use in audio, video, and similar equipment. This standard applies to certain types of auto transformers used in specific audio, video, and similar applications.
- UL 1446: Systems of Insulated Wires and Cables. This standard specifies requirements for the wire and cable systems used in transformers, including auto transformers, and ensures that they meet fire safety and electrical insulation criteria.
- UL 1012: Power units other than class 2. This standard covers electrical power supply devices, including auto transformers used in applications outside of class 2 devices.
3. CSA (Canadian Standards Association) Standards
In Canada, CSA sets the standards for electrical equipment, including transformers. Auto transformers must comply with CSA standards, such as:
- CSA C22.2 No. 0: General Requirements – Canadian Electrical Code. This code applies to electrical devices, including transformers, and establishes general safety and performance criteria.
- CSA C22.2 No. 14: Industrial Control Equipment. This standard may apply if the auto transformer is part of an industrial control system.
- CSA C22.2 No. 66: Electric Transformers. This standard governs transformers, including auto transformers, and addresses key safety and operational aspects.
4. Other Relevant Standards
In addition to the IEC, UL, and CSA standards, auto transformers might also comply with other regional or specialized standards depending on the application or industry. Some of these include:
- NEMA (National Electrical Manufacturers Association) Standards: For auto transformers used in North America, NEMA standards like NEMA MG-1 for motors and NEMA ST-1 for transformers may apply.
- ISO 9001: Quality management systems – This international standard ensures that the manufacturer of the auto transformer follows high-quality production and testing practices.
- IEEE (Institute of Electrical and Electronics Engineers) Standards: In certain cases, IEEE standards for transformers and electrical safety may apply.
Key Compliance Areas for Auto Transformers
The main areas in which Auto Transformers need to comply with these international standards include:
- Safety: Ensuring protection against electrical hazards, such as overcurrent, overload, and short circuits, as well as providing safe insulation levels and clearances.
- Electromagnetic Compatibility (EMC): Compliance with standards to minimize electromagnetic interference (EMI) and prevent malfunctioning of nearby electronics.
- Thermal Performance: Compliance with temperature rise tests, ensuring the auto transformer can operate safely within its rated temperature limits.
- Insulation: Ensuring that the insulation materials meet the specified dielectric strength and thermal properties as outlined by the relevant standards.
- Environmental Protection: Standards for protection against dust, moisture, and other environmental factors, ensuring the transformer operates reliably in various conditions.
- Energy Efficiency: In some markets, transformers, including auto transformers, must meet energy efficiency standards to reduce losses and ensure sustainability.
Conclusion
An Auto Transformer is generally designed to meet internationally recognized standards such as IEC, UL, CSA, and others, ensuring compliance with safety, quality, and performance requirements. These standards are crucial for guaranteeing the reliability and safety of the transformer in various operational environments, from industrial applications to residential and commercial uses.
Manufacturers typically test their auto transformers to ensure that they meet these standards, and often provide certification marks from recognized organizations (e.g., UL listing, IEC compliance) as proof of conformity. Therefore, when purchasing or using an auto transformer, it is essential to verify that it carries the appropriate certification for your region and application to ensure compliance and safety.
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